Welcome to the vObject land! This is a simple library that provides vanilla vObject routines and vCard/iCalendar implementations. To know more about vObject, vCard and iCalendar browse the other sections on the sidebar.
This library is an offspring of a need of mine. I was building a groupware application and did not want to make my app a friendless application, so I checked the net to see if there was any standard about groupware, most specifically contacts and calendar. You can't imagine my surprise when I discovered that both standards were indeed related and were very easy to understand. In the following weeks I created my routines and thought that people in the community might benefit from it. As of now, the library contains 154 functions and handlers dealing with every kind of need. This number will grow fast in the next releases, for this is just the low level stuff, higher level is coming. The generation of vCard and iCalendar now is done with high level functions, both got their own handler/function sets but parsing is done with plain vObject calls.
Notice: An understanding of the vObject format is needed before playing. This library is a direct implementation of the vCard and iCalendar RFC so the knowledge of those RFC is required to fully understand what is going on. Don't worry it's easier than you think, those RFCs are small. Knowing the property names and it's parameters is just what you need to generate and parse the files.
Included in this prroject vObjectLib which is the library, one or more demo stacks and this file with some docs and the RFCs. Beware that the source code of vObjectLib is fully commented and IS THE PRIME SOURCE OF DOCUMENTATION, each handler and function there got it's own multiline description with summary, parameter and return value descriptions.
Advise: please read the RFCs, this way you'll know how to generate everything.
This library is available as:
Andre Alves Garzia 5 de Abril de 2005 Niteroi, Brasil.
Andre Alves Garzia 18 of February, 2019 London, GB
The answer is simple, vObjects are portable and easy to understand. The task of parsing and generating vObject is easier then XML or *ML solutions. vObjects are portable across platforms and operating systems. vObjects are easy to integrate to popular internet protocols like HTTP and eMail.
A vObject (also refered some places as vFormat) is a text file that contains one or more vObject-like objects, this objects may contain more objects. It's a simple structured text file delimited by linefeeds, each line is a property, the objects are delimited by BEGIN and END tags. We could describe an orange using a hypotetical vFruit file like this:
BEGIN:VFRUIT
KIND:Orange
FORMAT:Spherical
VITAMINS:C
END:VFRUIT
See, there's the begin and end tags that enclose out vFruit object, each line is a property of this vFruit. The properties might contain more parameters than it's value, parameters are delimited by the semicolon char ";". An example of fruit with params:
BEGIN:VFRUIT
KIND;Origin=Brazil:Orange
FORMAT:Spherical
VITAMINS:C
END:VFRUIT
Our orange is now a Brazilian one, if someone query the value of the KIND prop will see the value "Orange" but if someone inspect the parameters of KIND will see an origin param with value Brazil. This is more usefull then you think, two examples will convince you. First binary data:
BEGIN:VCARD
FN:Andre Garzia
PHOTO;Encoding=Base64:AFGHDRHBSDRYHNVDRYNVF... Base64 Data...DRTDSRGCDF==
END:VCARD
This way your vCard contact file can carry binary data, the encoding param will tell the client app the correct way to unpack that property value. Other use is to differenciate same name props like phone numbers on vCard, see:
BEGIN:VCARD
FN:Andre Garzia
TEL;WORK:55 21 26095048
TEL;CELL:55 21 99581066
END:VCARD
The telephone properties above are tagged with valueless params, querying those params will return true for they are present (even if valueless), this way you can check and discover which is my mobile number and which is my work phone.
Properties can contain arbitrary number of parameters each delimited by the semicolon character, if the property value contains a semicolon, you should escape it.
The vObject Library provides functions to list parameters and properties, to alter then in any way you like. It's pretty straight forward. Also note that vObject files are supposed to have a max line lenght of 75 chars so there's a technique to serialize huge props so that it "folds" it. This is all covered in the library using the vObjectFold and vObjectUnfold routines. The folding is just puting a Space + LF every time the line reached 75 chars, unfolding just picks this Space + LF and makes them empty. So the vObject file is very human readable.
This library provides plain vObject routines and vCard and iCalendar routines built on top of those vanilla vObject handlers/functions. vCard is a format to carry contact data, iCalendar one to carry calendar and groupware data.
As of now, generation of vCard and iCalendar files is very high level but the parsing is done with plain vObject calls, but it's easy anyway, check the demos.
Should we say we eat our own vHaggis now?
This is the easier task of vObjectLib. Our vCards are compatible with version 3.0 of the spec. There are high level handlers for that but understanding the spec is good so that you can understand the amount of power you have on your hand. Let us create a simple vCard for storing my email settings.
put empty into vCard
vCardBegin vCard
vCardAddFullName vCard, "Andre Alves Garzia"
vCardAddName vCard, "Andre", "Garzia"
vCardAddEmail vCard, "andre@example.com"
vCardEnd vCard
vCardSerialize vCard
put vCard into URL "file:andregarzia.vcf"
It's done. We first create an empty chunk then we start by putting the begin header, then our data then the end header, after that we serialize (fold) the vObject/vCard. The content of this andregarzia.vcf is:
BEGIN:VCARD
FN:Andre Alves Garzia
N:Andre;Garzia;;;
EMAIL;TYPE=internet:andre@example.com
END:VCARD
you could just open it in Apple AddressBook and it would work fine. Check the RFCs for knowing what can you add to a vCard, also check the vObjectLib source code to see the handlers we prepared, we covered the full vCard 3.0 spec.
Let us create a non-standard vCard to carry the information of our beloved RunRev lists.
put empty into vCard
vCardBegin vCard
vCardAddFullName vCard, "How to Use Revolution."
vCardAddEmail vCard, "use-revolution@www.runrev.com"
vObjectAddParameter vCard, "email", "type", "group"
vCardEnd vCard
vCardBegin vCard
vCardAddFullName vCard, "Improve Revolution."
vCardAddEmail vCard, "improve-revolution@www.runrev.com"
vObjectAddParameter vCard, "email", "type", "group"
vCardEnd vCard
vCardSerialize vCard
The result would be:
BEGIN:VCARD
FN:How to Use Revolution.
EMAIL;TYPE=group;TYPE=internet:use-revolution@www.runrev.com
END:VCARD
BEGIN:VCARD
FN:Improve Revolution.
EMAIL;TYPE=group;TYPE=internet:improve-revolution@www.runrev.com
END:VCARD
A custom client would notice that this eMails got a Type Group and could take actions for mailing list addressess... Standard clients would just add the email normally, not knowing the Group parameter would not break the email property for standard clients. This is a huge advantage, this way you can put your own data on a vCard and guarantee that other apps will at least understand the standard part. This library vCard implementation only implement standard properties, but you can add your own using plain vObject calls.
Check the source code documentation for more info. But first, one final example.
put empty into vCard
vCardBegin vCard
vCardAddName vCard, "andre", "garzia"
vCardAddFullName vCard, "andre alves garzia"
vCardAddOrg vCard, "SoapDog Studio", "R&D dept"
vCardAddTitle vCard, "CTO"
vCardAddEmail vCard, "andre@example.com"
vObjectAddParameter vCard, "email", "type", "pref" -- Make it prefered eMail.
vObjectAddProperty vCard, "X-ABLabel", "Prefered eMail" -- Apple AddressBook non-standard label prop.
vObjectGroupProperties vCard, "item1", "email", "X-ABLabel"
## Apple AddressBook will match the email to the label, for they belong to the same group.
## Let's add more data...
vCardAddEmail vCard, "agarzia@mac.com"
vObjectAddProperty vCard, "X-ABLabel", "Alternate eMail" -- Apple AddressBook non-standard label prop.
vObjectGroupProperties vCard, "item2", "email", "X-ABLabel"
vCardAddNote vCard, "some notes on me, I am brazilian and I never quit..."
vCardEnd vCard
vCardSerialize vCard
This will render:
BEGIN:VCARD
N:andre;garzia;;;
FN:andre alves garzia
ORG:SoapDog Studio;R&D dept
TITLE:CTO
item1.EMAIL;TYPE=pref;TYPE=internet:andre@example.com
item1.X-ABLABEL:Prefered eMail
item2.EMAIL;TYPE=internet:agarzia@mac.com
item2.X-ABLABEL:Alternate eMail
NOTE:some notes on me\, I am brazilian and I never quit...
END:VCARD
As you know, vCards are special form of vObject that contains predefined properties and parameters which purpose is to carry contact data.
As of this first version, no high level function is ofered to parse vCards but the plain vObject routines do the job just fine. This of course will change very soon. The important functions for parsing vObjects are:
It returns the number of objects of a given type inside a vObject container. For example it can return the number of contacts inside a vCard object.
Example: answer vObjectCount("VCARD", allContacts) && "Contacts found inside object."
It splits a vObject into an array where each item corresponds to one object. With this you can split your huge vCard file containing all your contacts into an array where each member is a single contact.
Example:
put vObjectSplit("VCARD", allContacts) into tContactArrayA
answer "First object is:" & cr & tContactArrayA[1]
It will fetch a given object from inside a collection of objects, for example aquiring the first contact of a vCard file.
Example: put vObjectGet("vCard", allContacts, 1) into tFirstContact
it returns a property value, no matter if the property is grouped or if it contains parameters.
example: put GetvObjectPropertyValue(tFirstContact, "email") into tContactEmail
it returns a parameter value from a property, for example to check if the phone is a work phone use:
if getvObjectParamValue(tFirstContact, "tel", "work") then
put true into tIsWorkPhone
end if
this function will return the value of the parameter, case the parameter is empty but present it will return true, case it's missing then it will return false. vCard spec puts valueless parameters on props just to tag true and false values. The iCalendar spec does not use this kind of tagging scheme, it always put a value to a parameter.
Notice: The code for iCalendar parsing and generation is on the library file but I haven't written any documentation for it yet. Sorry. 14 years without documentation, argh.
Network Working Group T. Howes
Request for Comments: 2425 M. Smith
Category: Standards Track Netscape Communications Corp.
F. Dawson
Lotus Development Corporation
September 1998
A MIME Content-Type for Directory Information
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (1998). All Rights Reserved.
1. Abstract
This document defines a MIME Content-Type for holding directory
information. The definition is independent of any particular
directory service or protocol. The text/directory Content-Type is
defined for holding a variety of directory information, for example,
name, or email address, or logo. The text/directory Content-Type can
also be used as the root body part in a multipart/related Content-
Type for handling more complicated situations, especially those in
which non-textual information that already has a natural MIME
representation, for example, a photograph or sound, is to be
represented.
The text/directory Content-Type defines a general framework and
format for holding directory information in a simple "type:value"
form. We refer to "type" in this context meaning a property or
attribute with which the value is associated. Mechanisms are defined
to specify alternate languages, encodings and other meta-information.
This document also defines the procedure by which particular formats,
called profiles, for carrying application-specific information within
a text/directory Content-Type can be defined and registered, and the
conventions such formats must follow. It is expected that other
documents will be produced that define such formats for various
applications (e.g., white pages).
Howes, et. al. Standards Track [Page 1]
RFC 2425 MIME Content-Type for Directory Information September 1998
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY" and "OPTIONAL" in this
document are to be interpreted as described in [RFC-2119].
2. Table of Contents
Status of the Memo................................................ 1
Copyright Notice.................................................. 1
1. Abstract...................................................... 1
2. Table of Contents............................................. 2
3. Need for a MIME Directory Type................................ 3
4. Overview...................................................... 4
5. The text/directory Content-Type............................... 4
5.1. MIME media type name........................................ 4
5.2. MIME subtype name........................................... 5
5.3. Required parameters......................................... 5
5.4. Optional parameters......................................... 5
5.5. Encoding considerations..................................... 5
5.6. Security considerations..................................... 6
5.7. Interoperability considerations............................. 6
5.8. Published specification..................................... 6
5.8.1. Line delimiting and folding............................... 6
5.8.2. ABNF content-type definition.............................. 7
5.8.3. Pre-defined Parameters.................................... 9
5.8.4. Pre-defined Value Types...................................11
5.9. Applications which use this media type......................14
5.10. Additional information.....................................14
5.11. Person & email address to contact for further information..14
5.12. Intended usage.............................................14
5.13. Author/Change controller...................................15
6. Predefined Types..............................................15
6.1. SOURCE Type Definition......................................15
6.2. NAME Type Definition........................................16
6.3. PROFILE Type Definition.....................................16
6.4. BEGIN Type Definition.......................................17
6.5. END Type Definition.........................................17
7. Use of the multipart/related Content-Type.....................18
8. Examples.......................................................18
8.1. Example 1...................................................19
8.2. Example 2...................................................19
8.3. Example 3...................................................20
8.4. Example 4...................................................21
9. Registration of new profiles..................................22
9.1. Define the profile..........................................22
9.2. Post the profile definition.................................23
9.3. Allow a comment period......................................23
9.4. Submit the profile for approval.............................23
10. Profile Change Control.......................................23
Howes, et. al. Standards Track [Page 2]
RFC 2425 MIME Content-Type for Directory Information September 1998
11. Registration of new types....................................24
11.1. Define the type............................................24
11.2. Post the type definition...................................25
11.3. Allow a comment period.....................................25
11.4. Submit the type for approval...............................25
12. Type Change Control..........................................25
13. Registration of new parameters...............................26
13.1. Define the parameter.......................................26
13.2. Post the parameter definition..............................27
13.3. Allow a comment period.....................................27
13.4. Submit the parameter for approval..........................27
14. Parameter Change Control.....................................28
15. Registration of new value types..............................28
15.1. Define the value type......................................28
15.2. Post the value type definition.............................29
15.3. Allow a comment period.....................................29
15.4. Submit the value type for approval.........................29
16. Security Considerations......................................30
17. Acknowledgements..............................................30
18. References....................................................30
19. Authors' Addresses...........................................32
20. Full Copyright Statement......................................33
3. Need for a MIME Directory Type
For purposes of this document, a directory is a special-purpose
database that contains typed information. A directory usually
supports both read and search of the information it contains, and can
support creation and modification of the information as well.
Directory information is usually accessed far more often than it is
updated. Directories can be local or global in scope. They can be
distributed or centralized. The information they contain can be
replicated, with weak or strong consistency requirements.
There are several situations in which users of Internet mail might
wish to exchange directory information: the email analogy of a
"business card" exchange; the conveyance of directory information to
a user having only email access to the Internet; the provision of
machine-parseable address information when purchasing goods or
services over the Internet; etc. As MIME [RFC-2045, RFC-2046] is
used increasingly by other protocols, most notably HTTP, it can also
be useful for these protocols to carry directory information in MIME
format. Such a format, for example, could be used to represent URC
(uniform resource characteristics) information about resources on the
World Wide Web, or to provide a rudimentary directory service over
HTTP.
Howes, et. al. Standards Track [Page 3]
RFC 2425 MIME Content-Type for Directory Information September 1998
4. Overview
The scheme defined here for representing directory information in a
MIME Content-Type has two parts. First, the text/directory Content-
Type is defined for use in holding directory information within a
single body part, for example name, title, or email address. In its
simplest form, the format uses a "type:value" approach, which should
be easily parseable by existing MIME implementations and
understandable by users. More complicated situations can be
represented also. This document defines the general form the
information in the Content-Type should have, and the procedure by
which specific types and values (properties) for particular
applications can be defined. The framework is general enough to
handle information from any number of end directory services,
including LDAP [RFC-1777, RFC-1778], WHOIS++ [RFC-1835], and X.500
[X500].
Directory entries can include far more than just textual information.
Some such information (e.g., an image or sound) overlaps with
predefined MIME Content-Types. In these cases it can be desirable to
include the information in its well-known MIME format. This situation
is handled by using a multipart/related Content-Type as defined in
[RFC-2112]. The root component of this type is a text/directory body
part specifying any in-line information, and for information
contained in other Content-Types, the Content-IDs (in URI form) of
those parts.
In some applications, it can be useful to include a pointer (e.g, a
URI) to some directory information rather than the information
itself. This document defines a general mechanism for accomplishing
this.
5. The text/directory Content-Type
The text/directory Content-Type is used to hold basic directory
information and URIs referencing other information, including other
MIME body parts holding supplementary or non-textual directory
information, such as an image or sound. It is defined as follows,
using the MIME media type registration template from [RFC-2048].
To: ietf-types@uninett.no
Subject: Registration of MIME media type text/directory
5.1. MIME media type name
MIME media type name: text
Howes, et. al. Standards Track [Page 4]
RFC 2425 MIME Content-Type for Directory Information September 1998
5.2. MIME subtype name
MIME subtype name: directory
5.3. Required parameters
Required parameters: charset
The "charset" parameter is as defined in [RFC-2046] for other body
parts. It is used to identify the default character set used within
the body part.
5.4. Optional parameters
Optional parameters: profile
The "profile" parameter is used to convey the type(s) of entity(ies)
to which the directory information pertains and the likely set of
information associated with the entity(ies). It is intended only as a
guide to applications interpreting the information contained within
the body part. It SHOULD NOT be used to exclude or require particular
pieces of information unless a profile definition specifically calls
for this behavior. Unless specifically forbidden by a particular
profile definition, a text/directory content type can contain
arbitrary attribute/value pairs.
The value of the "profile" parameter is defined as follows. Profile
names are case insensitive (i.e., the profile name "vCard" is the
same as "VCARD" and "vcard" and "vcArD").
profile = x-name / iana-token
x-name = "x-" 1*(ALPHA / DIGIT / "-")
; Names beginning with "x-" or "X-" are
; reserved for experimental use not intended for released
; products, or for use in bilateral agreements.
iana-token = <a publicly-defined extension token, registered
with IANA, as specified in Section 9 of this
document>
5.5. Encoding considerations
The default encoding is 8bit. Otherwise, as specified by the
Content-Transfer-Encoding header field.
Howes, et. al. Standards Track [Page 5]
RFC 2425 MIME Content-Type for Directory Information September 1998
5.6. Security considerations
Directory information can be public or it can be protected from
unauthorized access by the directory service in which it resides.
Once the information leaves its native service, there can be no
guarantee that the same care will be taken by all services handling
the information. Furthermore, this specification defines no access
control mechanism by which information can be protected, or by which
access control information can be conveyed. Note that the integrity
and privacy of a text/directory body part can be protected by
enclosing it within an appropriate MIME-based security mechanism.
5.7. Interoperability considerations
In order to make sense of directory information, applications must
share a common understanding of the types of information contained
within the Content-Type (the directory schema). This schema
information is not defined in this document, but rather in companion
documents (e.g., [MIME-VCARD]) that follow the requirements specified
in this document, or in bilateral agreements between communicating
parties.
5.8. Published specification
The text/directory Content-Type contains directory information,
typically pertaining to a single directory entity or group of
entities. The content consists of one or more lines in the format
given below.
5.8.1. Line delimiting and folding
Individual lines within the MIME text/directory Content Type body are
delimited by the [RFC-822] line break, which is a CRLF sequence
(ASCII decimal 13, followed by ASCII decimal 10). Long logical lines
of text can be split into a multiple-physical-line representation
using the following folding technique.
A logical line MAY be continued on the next physical line anywhere
between two characters by inserting a CRLF immediately followed by a
single white space character (space, ASCII decimal 32, or horizontal
tab, ASCII decimal 9). At least one character must be present on the
folded line. Any sequence of CRLF followed immediately by a single
white space character is ignored (removed) when processing the
content type. For example the line:
DESCRIPTION:This is a long description that exists on a long line.
Can be represented as:
Howes, et. al. Standards Track [Page 6]
RFC 2425 MIME Content-Type for Directory Information September 1998
DESCRIPTION:This is a long description
that exists on a long line.
It could also be represented as:
DESCRIPTION:This is a long descrip
tion that exists o
n a long line.
The process of moving from this folded multiple-line representation
of a type definition to its single line representation is called
unfolding. Unfolding is accomplished by regarding CRLF immediately
followed by a white space character (namely HTAB ASCII decimal 9 or
SPACE ASCII decimal 32) as equivalent to no characters at all (i.e.,
the CRLF and single white space character are removed).
5.8.2. ABNF content-type definition
The following ABNF uses the notation of RFC 2234, which also defines
CRLF, WSP, DQUOTE, VCHAR, ALPHA, and DIGIT. After the unfolding of
any folded lines as described above, the syntax for a line of this
content type is as follows:
contentline = [group "."] name *(";" param) ":" value CRLF
; When parsing a content line, folded lines MUST first
; be unfolded according to the unfolding procedure
; described above.
; When generating a content line, lines longer than 75
; characters SHOULD be folded according to the folding
; procedure described above.
group = 1*(ALPHA / DIGIT / "-")
name = x-name / iana-token
iana-token = 1*(ALPHA / DIGIT / "-")
; identifier registered with IANA
x-name = "x-" 1*(ALPHA / DIGIT / "-")
; Names that begin with "x-" or "X-" are
; reserved for experimental use, not intended for released
; products, or for use in bilateral agreements.
param = param-name "=" param-value *("," param-value)
param-name = x-name / iana-token
param-value = ptext / quoted-string
Howes, et. al. Standards Track [Page 7]
RFC 2425 MIME Content-Type for Directory Information September 1998
ptext = *SAFE-CHAR
value = *VALUE-CHAR
/ valuespec ; valuespec defined in section 5.8.4
quoted-string = DQUOTE *QSAFE-CHAR DQUOTE
NON-ASCII = %x80-FF
; use restricted by charset parameter
; on outer MIME object (UTF-8 preferred)
QSAFE-CHAR = WSP / %x21 / %x23-7E / NON-ASCII
; Any character except CTLs, DQUOTE
SAFE-CHAR = WSP / %x21 / %x23-2B / %x2D-39 / %x3C-7E / NON-ASCII
; Any character except CTLs, DQUOTE, ";", ":", ","
VALUE-CHAR = WSP / VCHAR / NON-ASCII
; any textual character
A line that begins with a white space character is a continuation of
the previous line, as described above. The white space character and
immediately preceeding CRLF should be discarded when reconstructing
the original line. Note that this line-folding convention differs
from that found in RFC 822, in that the sequence <CRLF><WSP> found
anywhere in the content indicates a continued line and should be
removed.
Various type names and the format of the corresponding values are
defined as specified in Section 11. Specifications MAY impose
ordering on the type constructs within a body part, though none is
required by default. The various x-name constructs are used for
bilaterally-agreed upon type names, parameter names and parameter
values, or for use in experimental settings.
Type names and parameter names are case insensitive (e.g., the type
name "fn" is the same as "FN" and "Fn"). Parameter values MAY be case
sensitive or case insensitive, depending on their definition.
The group construct is used to group related attributes together.
The group name is a syntactic convention used to indicate that all
type names prefaced with the same group name SHOULD be grouped
together when displayed by an application. It has no other
significance. Implementations that do not understand or support
grouping MAY simply strip off any text before a "." to the left of
the type name and present the types and values as normal.
Howes, et. al. Standards Track [Page 8]
RFC 2425 MIME Content-Type for Directory Information September 1998
Each attribute defined in the text/directory body MAY have multiple
values, if allowed in the definition of the profile in which the
attribute is used. The general rule for encoding multi-valued items
is to simply create a new content line for each value (including the
type name). However, it should be noted that some value types
support encoding multiple values in a single content line by
separating the values with a comma ",". This approach has been taken
for several of the content types defined below (date, time, integer,
float), for space-saving reasons.
5.8.3. Pre-defined Parameters
The following parameters and value types are defined for general use.
predefined-param = encodingparm
/ valuetypeparm
/ languageparm
/ contextparm
encodingparm = "encoding" "=" encodingtype
encodingtype = "b" ; from RFC 2047
/ iana-token ; registered as described in
; section 15 of this document
valuetypeparm = "value" "=" valuetype
valuetype = "uri" ; genericurl from secion 5 of RFC 1738
/ "text"
/ "date"
/ "time"
/ "date-time" ; date time
/ "integer"
/ "boolean"
/ "float"
/ x-name
/ iana-token ; registered as described in
; section 15 of this document
languageparm = "language" "=" Language-Tag
; Language-Tag is defined in section 2 of RFC 1766
contextparm = "context" "=" context
context = x-name
/ iana-token
Howes, et. al. Standards Track [Page 9]
RFC 2425 MIME Content-Type for Directory Information September 1998
The "language" type parameter is used to identify data in multiple
languages. There is no concept of "default" language, except as
specified by any "Content-Language" MIME header parameter that is
present. The value of the "language" type parameter is a language
tag as defined in Section 2 of [RFC-1766].
The "context" type parameter is used to identify a context (e.g., a
protocol) used in interpreting the value. This is used, for example,
in the "source" type, defined below.
The "encoding" type parameter is used to specify an alternate
encoding for a value. If the value contains a CRLF, it must be
encoded, since CRLF is used to separate lines in the content-type
itself. Currently, only the "b" encoding is supported.
The "b" encoding can also be useful for binary values that are mixed
with other text information in the body part (e.g., a certificate).
Using a per-value "b" encoding in this case leaves the other
information in a more readable form. The encoded base 64 value can be
split across multiple physical lines in the content type by using the
line folding technique described above.
The Content-Transfer-Encoding header field is used to specify the
encoding used for the body part as a whole. The "encoding" type
parameter is used to specify an encoding for a particular value
(e.g., a certificate). In this case, the Content-Transfer-Encoding
header might specify "8bit", while the one certificate value might
specify an encoding of "b" via an "encoding=b" type parameter.
The Content-Transfer-Encoding and the encodings of individual types
given by the "encoding" type parameter are independent of one
another. When encoding a text/directory body part for transmission,
individual type encodings are performed first, then the entire body
part is encoded according to the Content-Transfer-Encoding. When
decoding a text/directory body part, the Content-Transfer-Encoding is
decoded first, and then any individual types with an "encoding" type
parameter are decoded.
The "value" parameter is optional, and is used to identify the value
type (data type) and format of the value. The use of these
predefined formats is encouraged even if the value parameter is not
explicity used. By defining a standard set of value types and their
formats, existing parsing and processing code can be leveraged.
Including the value type explicitly as part of each property provides
an extra hint to keep parsing simple and support more generalized
applications. For example a search engine would not have to know the
particular value types for all of the items for which it is
Howes, et. al. Standards Track [Page 10]
RFC 2425 MIME Content-Type for Directory Information September 1998
searching. Because the value type is explicit in the definition, the
search engine could look for dates in any item type and provide
results that can still be interpreted.
5.8.4. Pre-defined Value Types
The format for values corresponding to the predefined valuetype
specifications given above are defined.
valuespec = text-list
/ genericurl ; from section 5 of RFC 1738
/ date-list
/ time-list
/ date-time-list
/ boolean
/ integer-list
/ float-list
/ iana-valuespec
text-list = *TEXT-LIST-CHAR *("," *TEXT-LIST-CHAR)
TEXT-LIST-CHAR = "\\" / "\," / "\n"
/ <any VALUE-CHAR except , or \ or newline>
; Backslashes, newlines, and commas must be encoded.
; \n or \N can be used to encode a newline.
date-list = date *("," date)
time-list = time *("," time)
date-time-list = date "T" time *("," date "T" time)
boolean = "TRUE" / "FALSE"
integer-list = integer *("," integer)
integer = [sign] 1*DIGIT
float-list = float *("," float)
float = [sign] 1*DIGIT ["." 1*DIGIT]
sign = "+" / "-"
date = date-fullyear ["-"] date-month ["-"] date-mday
date-fullyear = 4 DIGIT
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RFC 2425 MIME Content-Type for Directory Information September 1998
date-month = 2 DIGIT ;01-12
date-mday = 2 DIGIT ;01-28, 01-29, 01-30, 01-31
;based on month/year
time = time-hour [":"] time-minute [":"] time-second [time-secfrac]
[time-zone]
time-hour = 2 DIGIT ;00-23
time-minute = 2 DIGIT ;00-59
time-second = 2 DIGIT ;00-60 (leap second)
time-secfrac = "," 1*DIGIT
time-zone = "Z" / time-numzone
time-numzome = sign time-hour [":"] time-minute
iana-valuespec = <a publicly-defined valuetype format, registered
with IANA, as defined in section 15 of this
document>
Some specific notes on the value types and formats:
"text": The "text" value type should be used to identify values that
contain human-readable text. The character set and language in which
the text is represented is controlled by the charset content-header
and the language type parameter and content-header.
Examples for "text":
this is a text value
this is one value,this is another
this is a single value\, with a comma encoded
A formatted text line break in a text value type MUST be represented
as the character sequence backslash (ASCII decimal 92) followed by a
Latin small letter n (ASCII decimal 110) or a Latin capital letter N
(ASCII decimal 78), that is "\n" or "\N".
For example a multiple line DESCRIPTION value of:
Mythical Manager
Hyjinx Software Division
BabsCo, Inc.
could be represented as:
Howes, et. al. Standards Track [Page 12]
RFC 2425 MIME Content-Type for Directory Information September 1998
DESCRIPTION:Mythical Manager\nHyjinx Software Division\n
BabsCo\, Inc.\n
demonstrating the \n literal formatted line break technique, the
CRLF-followed-by-space line folding technique, and the backslash
escape technique.
"uri": The "uri" value type should be used to identify values that
are referenced by a URI (including a Content-ID URI), instead of
encoded in-line. These value references might be used if the value is
too large, or otherwise undesirable to include directly. The format
for the URI is as defined in RFC 1738.
Examples for "uri":
http://www.foobar.com/my/picture.jpg
ldap://ldap.foobar.com/cn=babs%20jensen
"date", "time", and "date-time": Each of these value types is based
on a subset of the definitions in ISO 8601 standard. Profiles MAY
place further restrictions on "date" and "time" values. Multiple
"date" and "time" values can be specified using the comma-separated
notation, unless restricted by a profile.
Examples for "date":
1985-04-12
1996-08-05,1996-11-11
19850412
Examples for "time":
10:22:00
102200
10:22:00.33
10:22:00.33Z
10:22:33,11:22:00
10:22:00-08:00
Examples for "date-time":
1996-10-22T14:00:00Z
1996-08-11T12:34:56Z
19960811T123456Z
1996-10-22T14:00:00Z,1996-08-11T12:34:56Z
"boolean": The "boolean" value type is used to express boolen values.
These values are case insensitive.
Examples: TRUE
false
True
Howes, et. al. Standards Track [Page 13]
RFC 2425 MIME Content-Type for Directory Information September 1998
"integer": The "integer" value type is used to express signed
integers in decimal format. If sign is not specified, the value is
assumed positive "+". Multiple "integer" values can be specified
using the comma-separated notation, unless restricted by a profile.
Examples: 1234567890
-1234556790
+1234556790,432109876
"float": The "float" value type is used to express real numbers. If
sign is not specified, the value is assumed positive "+". Multiple
"float" values can be specified using the comma-separated notation,
unless restricted by a profile.
Examples: 20.30
1000000.0000001
1.333,3.14
5.9. Applications which use this media type
Applications which use this media type: Various
5.10. Additional information
Additional information: None
5.11. Person & email address to contact for further information
Tim Howes
Netscape Communications Corp.
501 East Middlefield Rd.
Mountain View, CA 94041
USA
howes@netscape.com
+1 415 937 3419
5.12. Intended usage
Intended usage: COMMON
Howes, et. al. Standards Track [Page 14]
RFC 2425 MIME Content-Type for Directory Information September 1998
5.13. Author/Change controller
Tim Howes
Netscape Communications Corp.
501 East Middlefield Rd.
Mountain View, CA 94041
USA
howes@netscape.com
+1 415 937 3419
Mark Smith
Netscape Communications Corp.
501 East Middlefield Rd.
Mountain View, CA 94041
USA
mcs@netscape.com
+1 415 937 3477
Frank Dawson
Lotus Development Corporation
6544 Battleford Drive
Raleigh, NC 27613-3502
USA
frank_dawson@lotus.com
+1-919-676-9515
6. Predefined Types
The following types are generally useful regardless of the profile
being carried and are defined below using the text/directory MIME
type registration template defined in Section 11.1 of this document.
These types MAY be included in any profile, unless explicitly
forbidden in the profile definition.
6.1. SOURCE Type Definition
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME type SOURCE
Type name: SOURCE
Type purpose: To identify the source of directory information
contained in the content type.
Type encoding: 8bit
Type valuetype: uri
Howes, et. al. Standards Track [Page 15]
RFC 2425 MIME Content-Type for Directory Information September 1998
Type special notes: The SOURCE type is used to provide the means by
which applications knowledgable in the given directory service
protocol can obtain additional or more up-to-date information from
the directory service. It contains a URI as defined in [RFC-1738]
and/or other information referencing the directory entity or entities
to which the information pertains. When directory information is
available from more than one source, the sending entity can pick what
it considers to be the best source, or multiple SOURCE types can be
included. The interpretation of the value for a SOURCE type can
depend on the setting of the CONTEXT type parameter. The value of the
CONTEXT type parameter MUST be compatible with the value of the uri
prefix.
Type example:
SOURCE;CONTEXT=LDAP:ldap://ldap.host/cn=Babs%20Jensen,
%20o=Babsco,%20c=US
6.2. NAME Type Definition
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME type NAME
Type name: NAME
Type purpose: To identify the displayable name of the directory
entity to which information in the content type pertains.
Type encoding: 8bit
Type valuetype: text
Type special notes: The NAME type is used to convey the display name
of the entity to which the directory information pertains.
Type example:
NAME:Babs Jensen's Contact Information
6.3. PROFILE Type Definition
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME type PROFILE
Type name: PROFILE
Type purpose: To identify the type of directory entity to which
information in the content type pertains.
Type encoding: 8bit
Howes, et. al. Standards Track [Page 16]
RFC 2425 MIME Content-Type for Directory Information September 1998
Type valuetype: A profile name, registered as described in Section 9
of this document or bilaterally agreed upon as described in Section
5.
Type special notes: The PROFILE type is used to convey the type of
the entity to which the directory information in the rest of the body
part pertains. It should be the same as the "profile" header
parameter, if present.
Type example:
PROFILE:vCard
6.4. BEGIN Type Definition
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME type BEGIN
Type name: BEGIN
Type purpose: To denote the beginning of a syntactic entity within a
text/directory content-type.
Type encoding: 8bit
Type valuetype: text, containing a profile name, registered as
described in Section 9 of this document or bilaterally-agreed upon as
described in Section 5.
Type special notes: The BEGIN type is used in conjunction with the
END type to delimit a profile containing a related set of properties
within an text/directory content-type. This construct can be used
instead of or in addition to wrapping separate sets of information
inside additional MIME headers. It is provided for applications that
wish to define content that can contain multiple entities within the
same text/directory content-type or to define content that can be
identifiable outside of a MIME environment.
Type example:
BEGIN:VCARD
6.5. END Type Definition
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME type END
Type name: END
Howes, et. al. Standards Track [Page 17]
RFC 2425 MIME Content-Type for Directory Information September 1998
Type purpose: To denote the end of a syntactic entity within a
text/directory content-type.
Type encoding: 8bit
Type valuetype: text, containing a profile name, registered as
described in Section 9 of this document or bilaterally-agreed upon as
described in Section 5.
Type special notes: The END type is used in conjunction with the
BEGIN type to delimit a profile containing a related set of
properties within an text/directory content-type. This construct can
be used instead of or in addition to wrapping separate sets of
information inside additional MIME headers. It is provided for
applications that wish to define content that can contain multiple
entities within the same text/directory content-type or to define
content that can be identifiable outside of a MIME environment.
Type example:
END: VCARD
7. Use of the multipart/related Content-Type
The multipart/related Content-Type can be used to hold directory
information comprised of both text and non-text information or
directory information that already has a natural MIME representation.
The root body part within the multipart/related body part is
specified as defined in [RFC-2112] by a "start" parameter, or it is
the first body part in the absence of such a parameter. The root
body part must have a Content-Type of "text/directory". This part
holds inline information and makes reference to subsequent body parts
holding additional text or non-text directory information via their
Content-ID URIs as explained in Section 5.
The body parts referred to do not have to be in any particular order,
except as noted above for the root body part.
8. Examples
The following examples are for illustrative purposes only and are not
part of the definition.
Howes, et. al. Standards Track [Page 18]
RFC 2425 MIME Content-Type for Directory Information September 1998
8.1. Example 1
The first example illustrates simple use of the text/directory
Content-Type. Note that no "profile" parameter is given, so an
application may not know what kind of directory entity the
information applies to. Note also the use of both hypothetical
official and bilaterally agreed upon types.
From: Whomever@wherever.com
To: Someone@somewhere.com
Subject: whatever
MIME-Version: 1.0
Message-ID: <id1@host.net>
Content-Type: text/directory
Content-ID: <id2@host.com>
cn:Babs Jensen
cn:Barbara J Jensen
sn:Jensen
email:babs@umich.edu
phone:+1 313 747-4454
x-id:1234567890
8.2. Example 2
The next example illustrates the use of the Quoted-Printable transfer
encoding defined in [RFC 2045] to include non-ASCII character in some
of the information returned, and the use of the optional "name" and
"source" types. It also illustrates the use of an "encoding" type
parameter to encode a certificate value in "b". A "vCard" profile
[MIME- VCARD] is used for the example.
Content-Type: text/directory;
charset="iso-8859-1";
profile="vCard"
Content-ID: <id3@host.com>
Content-Transfer-Encoding: Quoted-Printable
begin:VCARD
source:ldap://cn=bjorn%20Jensen, o=university%20of%20Michigan, c=US
name:Bjorn Jensen
fn:Bj=F8rn Jensen
n:Jensen;Bj=F8rn
email;type=internet:bjorn@umich.edu
tel;type=work,voice,msg:+1 313 747-4454
key;type=x509;encoding=B:dGhpcyBjb3VsZCBiZSAKbXkgY2VydGlmaWNhdGUK
end:VCARD
Howes, et. al. Standards Track [Page 19]
RFC 2425 MIME Content-Type for Directory Information September 1998
8.3. Example 3
The next example illustrates the use of multi-valued type parameters,
the "language" type parameter, the "value" type parameter, folding of
long lines, the \n encoding for formatted lines, attribute grouping,
and the inline "b" encoding. A "vCard" profile [MIME-VCARD] is used
for the example.
Content-Type: text/directory; profile="vcard"; charset=iso-8859-1
Content-ID: <id3@host.com>
Content-Transfer-Encoding: Quoted-Printable
begin:vcard
source:ldap://cn=Meister%20Berger,o=Universitaet%20Goerlitz,c=DE
name:Meister Berger
fn:Meister Berger
n:Berger;Meister
bday;value=date:1963-09-21
o:Universit=E6t G=F6rlitz
title:Mayor
title;language=de;value=text:Burgermeister
note:The Mayor of the great city of
Goerlitz in the great country of Germany.
email;internet:mb@goerlitz.de
home.tel;type=fax,voice,msg:+49 3581 123456
home.label:Hufenshlagel 1234\n
02828 Goerlitz\n
Deutschland
key;type=X509;encoding=b:MIICajCCAdOgAwIBAgICBEUwDQYJKoZIhvcNAQEEBQ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end:vcard
Howes, et. al. Standards Track [Page 20]
RFC 2425 MIME Content-Type for Directory Information September 1998
8.4. Example 4
The final example illustrates the use of the multipart/related
Content-Type to include non-textual directory data via the "uri"
encoding to refer to other body parts within the same message, or to
external values. Note that no "profile" parameter is given, so an
application may not know what kind of directory entity the
information applies to. Note also the use of both hypothetical
official and bilaterally agreed upon types.
Content-Type: multipart/related;
boundary=woof;
type="text/directory";
start="<id5@host.com>"
Content-ID: <id4@host.com>
--woof
Content-Type: text/directory; charset="iso-8859-1"
Content-ID: <id5@host.com>
Content-Transfer-Encoding: Quoted-Printable
source:ldap://cn=Bjorn%20Jensen,o=University%20of%20Michigan,c=US
cn:Bj=F8rn Jensen
sn:Jensen
email:bjorn@umich.edu
image;value=uri:cid:id6@host.com
image;value=uri;format=jpeg:ftp://some.host/some/path.jpg
sound;value=uri:cid:id7@host.com
phone:+1 313 747-4454
--woof
Content-Type: image/jpeg
Content-ID: <id6@host.com>
<...image data...>
--woof
Content-Type: message/external-body;
name="myvoice.au";
site="myhost.com";
access-type=ANON-FTP;
directory="pub/myname";
mode="image"
Content-Type: audio/basic
Content-ID: <id7@host.com>
--woof--
Howes, et. al. Standards Track [Page 21]
RFC 2425 MIME Content-Type for Directory Information September 1998
9. Registration of new profiles
This section defines procedures by which new profiles are registered
with the IANA and made available to the Internet community. Note that
non-IANA profiles can be used by bilateral agreement, provided the
associated profile names follow the "X-" convention defined above.
The procedures defined here are designed to allow public comment and
review of new profiles, while posing only a small impediment to the
definition of new profiles.
Registration of a new profile is accomplished by the following steps.
9.1. Define the profile
A profile is defined by completing the following template.
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME profile XXX
Profile name:
Profile purpose:
Profile types:
Profile special notes (optional):
Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)
The explanation of what goes in each field in the template follows.
Profile name: The name of the profile as it will appear in the
text/directory MIME Content-Type "profile" header parameter, or the
predefined "profile" type name.
Profile purpose: The purpose of the profile (e.g., to represent
information about people, printers, documents, etc.). Give a short
but clear description.
Profile types: The list of types associated with the profile. This
list of types is to be expected but not required in the profile,
unless otherwise noted in the profile definition. Other types not
mentioned in the profile definition MAY also be present. Note that
any new types referenced by the profile MUST be defined separately as
described in Section 10.
Howes, et. al. Standards Track [Page 22]
RFC 2425 MIME Content-Type for Directory Information September 1998
Profile special notes: Any special notes about the profile, how it is
to be used, etc. This section of the template can also be used to
define an ordering on the types that appear in the Content-Type, if
such an ordering is required.
9.2. Post the profile definition
The profile description must be posted to the new profile discussion
list, ietf-mime-direct@imc.org
9.3. Allow a comment period
Discussion on the new profile must be allowed to take place on the
list for a minimum of two weeks. Consensus must be reached on the
profile before proceeding to step 4.
9.4. Submit the profile for approval
Once the two-week comment period has elapsed, and the proposer is
convinced consensus has been reached on the profile, the registration
application should be submitted to the Profile Reviewer for approval.
The Profile Reviewer is appointed by the Application Area Directors
and can either accept or reject the profile registration. An accepted
registration is passed on by the Profile Reviewer to the IANA for
inclusion in the official IANA profile registry. The registration may
be rejected for any of the following reasons. 1) Insufficient comment
period; 2) Consensus not reached; 3) Technical deficiencies raised on
the list or elsewhere have not been addressed. The Profile Reviewer's
decision to reject a profile can be appealed by the proposer to the
IESG, or the objections raised can be addressed by the proposer and
the profile resubmitted.
10. Profile Change Control
Existing profiles can be changed using the same process by which they
were registered.
Define the change
Post the change
Allow a comment period
Submit the changed profile for approval
Howes, et. al. Standards Track [Page 23]
RFC 2425 MIME Content-Type for Directory Information September 1998
Note that the original author or any other interested party can
propose a change to an existing profile, but that such changes should
only be proposed when there are serious omissions or errors in the
published specification. The Profile Reviewer can object to a change
if it is not backwards compatible, but is not required to do so.
Profile definitions can never be deleted from the IANA registry, but
profiles which are no longer believed to be useful can be declared
OBSOLETE by a change to their "intended use" field.
11. Registration of new types
This section defines procedures by which new types are registered
with the IANA. Note that non-IANA types can be used by bilateral
agreement, provided the associated types names follow the "X-"
convention defined above.
The procedures defined here are designed to allow public comment and
review of new types, while posing only a small impediment to the
definition of new types.
Registration of a new type is accomplished by the following steps.
11.1. Define the type
A type is defined by completing the following template.
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME type XXX
Type name:
Type purpose:
Type encoding:
Type valuetype:
Type special notes (optional):
Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)
The meaning of each field in the template is as follows.
Type name: The name of the type, as it will appear in the body of an
text/directory MIME Content-Type "type: value" line to the left of
the colon ":".
Howes, et. al. Standards Track [Page 24]
RFC 2425 MIME Content-Type for Directory Information September 1998
Type purpose: The purpose of the type (e.g., to represent a name,
postal address, IP address, etc.). Give a short but clear
description.
Type encoding: The default encoding a value of the type must have in
the body of a text/directory MIME Content-Type.
Type valuetype: The format a value of the type must have in the body
of a text/directory MIME Content-Type. This description must be
precise and must not violate the general encoding rules defined in
section 5 of this document.
Type special notes: Any special notes about the type, how it is to be
used, etc.
11.2. Post the type definition
The type description must be posted to the new type discussion list,
ietf-mime-direct@imc.org
11.3. Allow a comment period
Discussion on the new type must be allowed to take place on the list
for a minimum of two weeks. Consensus must be reached on the type
before proceeding to step 4.
11.4. Submit the type for approval
Once the two-week comment period has elapsed, and the proposer is
convinced consensus has been reached on the type, the registration
application should be submitted to the Profile Reviewer for approval.
The Profile Reviewer is appointed by the Application Area Directors
and can either accept or reject the type registration. An accepted
registration is passed on by the Profile Reviewer to the IANA for
inclusion in the official IANA profile registry. The registration can
be rejected for any of the following reasons. 1) Insufficient comment
period; 2) Consensus not reached; 3) Technical deficiencies raised on
the list or elsewhere have not been addressed. The Profile
Reviewer's decision to reject a type can be appealed by the proposer
to the IESG, or the objections raised can be addressed by the
proposer and the type resubmitted.
Howes, et. al. Standards Track [Page 25]
RFC 2425 MIME Content-Type for Directory Information September 1998
12. Type Change Control
Existing types can be changed using the same process by which they
were registered.
Define the change
Post the change
Allow a comment period
Submit the type for approval
Note that the original author or any other interested party can
propose a change to an existing type, but that such changes should
only be proposed when there are serious omissions or errors in the
published specification. The Profile Reviewer can object to a change
if it is not backwards compatible, but is not required to do so.
Type definitions can never be deleted from the IANA registry, but
types which are nolonger believed to be useful can be declared
OBSOLETE by a change to their "intended use" field.
13. Registration of new parameters
This section defines procedures by which new parameters are
registered with the IANA and made available to the Internet
community. Note that non-IANA parameters can be used by bilateral
agreement, provided the associated parameters names follow the "X-"
convention defined above.
The procedures defined here are designed to allow public comment and
review of new parameters, while posing only a small impediment to the
definition of new parameters.
Registration of a new parameter is accomplished by the following
steps.
13.1. Define the parameter
A parameter is defined by completing the following template.
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME type parameter XXX
Parameter name:
Parameter purpose:
Howes, et. al. Standards Track [Page 26]
RFC 2425 MIME Content-Type for Directory Information September 1998
Parameter values:
Parameter special notes (optional):
Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)
The explanation of what goes in each field in the template follows.
Parameter name: The name of the parameter as it will appear in the
text/directory MIME Content-Type.
Parameter purpose: The purpose of the parameter (e.g., to represent
the format of an image, type of a phone number, etc.). Give a short
but clear description. If defining a general paramemter like "format"
or "type" keep in mind that other applications might wish to extend
its use.
Parameter values: The list or description of values associated with
the parameter.
Parameter special notes: Any special notes about the parameter, how
it is to be used, etc.
13.2. Post the parameter definition
The parameter description must be posted to the new parameter
discussion list, ietf-mime-direct@imc.org
13.3. Allow a comment period
Discussion on the new parameter must be allowed to take place on the
list for a minimum of two weeks. Consensus must be reached on the
parameter before proceeding to step 4.
13.4. Submit the parameter for approval
Once the two-week comment period has elapsed, and the proposer is
convinced consensus has been reached on the parameter, the
registration application should be submitted to the Profile Reviewer
for approval. The Profile Reviewer is appointed by the Application
Area Directors and can either accept or reject the parameter
registration. An accepted registration is passed on by the Profile
Reviewer to the IANA for inclusion in the official IANA parameter
registry. The registration can be rejected for any of the following
reasons. 1) Insufficient comment period; 2) Consensus not reached; 3)
Technical deficiencies raised on the list or elsewhere have not been
addressed. The Profile Reviewer's decision to reject a profile can be
appealed by the proposer to the IESG, or the objections raised can be
Howes, et. al. Standards Track [Page 27]
RFC 2425 MIME Content-Type for Directory Information September 1998
addressed by the proposer and the parameter registration resubmitted.
14. Parameter Change Control
Existing parameters can be changed using the same process by which
they were registered.
Define the change
Post the change
Allow a comment period
Submit the parameter for approval
Note that the original author or any other interested party can
propose a change to an existing parameter, but that such changes
should only be proposed when there are serious omissions or errors in
the published specification. The Profile Reviewer can object to a
change if it is not backwards compatible, but is not required to do
so.
Parameter definitions can never be deleted from the IANA registry,
but parameters which are nolonger believed to be useful can be
declared OBSOLETE by a change to their "intended use" field.
15. Registration of new value types
This section defines procedures by which new value types are
registered with the IANA and made available to the Internet
community. Note that non-IANA value types can be used by bilateral
agreement, provided the associated value types names follow the "X-"
convention defined above.
The procedures defined here are designed to allow public comment and
review of new value types, while posing only a small impediment to
the definition of new value types.
Registration of a new value types is accomplished by the following
steps.
15.1. Define the value type
A value type is defined by completing the following template.
To: ietf-mime-direct@imc.org
Subject: Registration of text/directory MIME value type XXX
Howes, et. al. Standards Track [Page 28]
RFC 2425 MIME Content-Type for Directory Information September 1998
value type name:
value type purpose:
value type format:
value type special notes (optional):
Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)
The explanation of what goes in each field in the template follows.
value type name: The name of the value type as it will appear in the
text/directory MIME Content-Type.
value type purpose: The purpose of the value type. Give a short but
clear description.
value type format: The definition of the format for the value,
usually using ABNF grammar.
value type special notes: Any special notes about the value type, how
it is to be used, etc.
15.2. Post the value type definition
The value type description must be posted to the new value type
discussion list, ietf-mime-direct@imc.org
15.3. Allow a comment period
Discussion on the new value type must be allowed to take place on the
list for a minimum of two weeks. Consensus must be reached before
proceeding to step 4.
15.4. Submit the value type for approval
Once the two-week comment period has elapsed, and the proposer is
convinced consensus has been reached on the value type, the
registration application should be submitted to the Profile Reviewer
for approval. The Profile Reviewer is appointed by the Application
Area Directors and can either accept or reject the value type
registration. An accepted registration should be passed on by the
Profile Reviewer to the IANA for inclusion in the official IANA value
type registry. The registration can be rejected for any of the
following reasons. 1) Insufficient comment period; 2) Consensus not
reached; 3) Technical deficiencies raised on the list or elsewhere
have not been addressed. The Profile Reviewer's decision to reject a
Howes, et. al. Standards Track [Page 29]
RFC 2425 MIME Content-Type for Directory Information September 1998
profile can be appealed by the proposer to the IESG, or the
objections raised can be addressed by the proposer and the value type
registration resubmitted.
16. Security Considerations
Internet mail is subject to many well known security attacks,
including monitoring, replay, and forgery. Care should be taken by
any directory service in allowing information to leave the scope of
the service itself, where any access controls can no longer be
guaranteed. Applications should also take care to display directory
data in a "safe" environment (e.g., PostScript-valued types).
17. Acknowledgements
The registration procedures defined here were shamelessly lifted from
the MIME registration RFC.
The many valuable comments contributed by members of the IETF ASID
working group are gratefully acknowledged, as are the contributions
of the Versit Consortium. Chris Newman was especially helpful in
navigating the intricacies of ABNF lore.
18. References
[RFC-1777] Yeong, W., Howes, T., and S. Kille, "Lightweight
Directory Access Protocol", RFC 1777, March 1995.
[RFC-1778] Howes, T., Kille, S., Yeong, W., and C. Robbins, "The
String Representation of Standard Attribute Syntaxes",
RFC 1778, March 1995.
[RFC-822] Crocker, D., "Standard for the Format of ARPA Internet
Text Messages", STD 11, RFC 822, August 1982.
[RFC-2045] Borenstein, N., and N. Freed, "Multipurpose Internet
Mail Extensions (MIME) Part One: Format of Internet
Message Bodies", RFC 2045, November 1996.
[RFC-2046] Moore, K., "Multipurpose Internet Mail Extensions (MIME)
Part Two: Media Types", RFC 2046, November 1996.
[RFC-2048] Freed, N., Klensin, J., and J. Postel, "Multipurpose
Internet Mail Extensions (MIME) Part Four: Registration
Procedures", RFC 2048, November 1996.
[RFC-1766] Alvestrand, H., "Tags for the Identification of
Languages", RFC 1766, March 1995.
Howes, et. al. Standards Track [Page 30]
RFC 2425 MIME Content-Type for Directory Information September 1998
[RFC-2112] Levinson, E., "The MIME Multipart/Related Content-type",
RFC 2112, March 1997.
[X500] "Information Processing Systems - Open Systems
Interconnection - The Directory: Overview of Concepts,
Models and Services", ISO/IEC JTC 1/SC21, International
Standard 9594-1, 1988.
[RFC-1835] Deutsch, P., Schoultz, R., Faltstrom, P., and C. Weider,
"Architecture of the WHOIS++ service", RFC 1835, August
1995.
[RFC-1738] Berners-Lee, T., Masinter, L., and M. McCahill, "Uniform
Resource Locators (URL)", RFC 1738, December 1994.
[MIME-VCARD] Dawson, F., and T. Howes, "VCard MIME Directory
Profile", RFC 2426, September 1998.
[VCARD] Internet Mail Consortium, "vCard - The Electronic
Business Card", Version 2.1,
http://www.imc.com/pdi/vcard-21.txt, September, 1996.
[RFC-2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC-2234] Crocker, D., and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
Howes, et. al. Standards Track [Page 31]
RFC 2425 MIME Content-Type for Directory Information September 1998
19. Authors' Addresses
Tim Howes
Netscape Communications Corp.
501 East Middlefield Rd.
Mountain View, CA 94041
USA
Phone: +1.415.937.3419
EMail: howes@netscape.com
Mark Smith
Netscape Communications Corp.
501 East Middlefield Rd.
Mountain View, CA 94041
USA
Phone: +1.415.937.3477
EMail: mcs@netscape.com
Frank Dawson
Lotus Development Corporation
6544 Battleford Drive
Raleigh, NC 27613
USA
Phone: +1-919-676-9515
EMail: frank_dawson@lotus.com
Howes, et. al. Standards Track [Page 32]
RFC 2425 MIME Content-Type for Directory Information September 1998
20. Full Copyright Statement
Copyright (C) The Internet Society (1998). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Howes, et. al. Standards Track [Page 33]
Network Working Group F. Dawson
Request for Comments: 2426 Lotus Development Corporation
Category: Standards Track T. Howes
Netscape Communications
September 1998
vCard MIME Directory Profile
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (1998). All Rights Reserved.
Abstract
This memo defines the profile of the MIME Content-Type [MIME-DIR] for
directory information for a white-pages person object, based on a
vCard electronic business card. The profile definition is independent
of any particular directory service or protocol. The profile is
defined for representing and exchanging a variety of information
about an individual (e.g., formatted and structured name and delivery
addresses, email address, multiple telephone numbers, photograph,
logo, audio clips, etc.). The directory information used by this
profile is based on the attributes for the person object defined in
the X.520 and X.521 directory services recommendations. The profile
also provides the method for including a [VCARD] representation of a
white-pages directory entry within the MIME Content-Type defined by
the [MIME-DIR] document.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY" and "OPTIONAL" in this
document are to be interpreted as described in [RFC 2119].
Dawson & Howes Standards Track [Page 1]
RFC 2426 vCard MIME Directory Profile September 1998
Table of Contents
Overview.........................................................3
1. THE VCARD MIME DIRECTORY PROFILE REGISTRATION.................4
2. MIME DIRECTORY FEATURES.......................................5
2.1 PREDEFINED TYPE USAGE ......................................5
2.1.1 BEGIN and END Type ......................................5
2.1.2 NAME Type ...............................................5
2.1.3 PROFILE Type ............................................5
2.1.4 SOURCE Type .............................................5
2.2 PREDEFINED TYPE PARAMETER USAGE ............................6
2.3 PREDEFINED VALUE TYPE USAGE ................................6
2.4 EXTENSIONS TO THE PREDEFINED VALUE TYPES ...................6
2.4.1 BINARY ..................................................6
2.4.2 VCARD ...................................................6
2.4.3 PHONE-NUMBER ............................................7
2.4.4 UTC-OFFSET ..............................................7
2.5 STRUCTURED TYPE VALUES .....................................7
2.6 LINE DELIMITING AND FOLDING ................................8
3. VCARD PROFILE FEATURES........................................8
3.1 IDENTIFICATION TYPES .......................................8
3.1.1 FN Type Definition ......................................8
3.1.2 N Type Definition .......................................9
3.1.3 NICKNAME Type Definition ................................9
3.1.4 PHOTO Type Definition ..................................10
3.1.5 BDAY Type Definition ...................................11
3.2 DELIVERY ADDRESSING TYPES .................................11
3.2.1 ADR Type Definition ....................................11
3.2.2 LABEL Type Definition ..................................13
3.3 TELECOMMUNICATIONS ADDRESSING TYPES .......................13
3.3.1 TEL Type Definition ....................................14
3.3.2 EMAIL Type Definition ..................................15
3.3.3 MAILER Type Definition .................................15
3.4 GEOGRAPHICAL TYPES ........................................16
3.4.1 TZ Type Definition .....................................16
3.4.2 GEO Type Definition ....................................16
3.5 ORGANIZATIONAL TYPES ......................................17
3.5.1 TITLE Type Definition ..................................17
3.5.2 ROLE Type Definition ...................................18
3.5.3 LOGO Type Definition ...................................18
3.5.4 AGENT Type Definition ..................................19
3.5.5 ORG Type Definition ....................................20
3.6 EXPLANATORY TYPES .........................................20
3.6.1 CATEGORIES Type Definition .............................20
3.6.2 NOTE Type Definition ...................................21
3.6.3 PRODID Type Definition .................................21
3.6.4 REV Type Definition ....................................22
3.6.5 SORT-STRING Type Definition ............................22
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RFC 2426 vCard MIME Directory Profile September 1998
3.6.6 SOUND Type Definition ..................................23
3.6.7 UID Type Definition ....................................24
3.6.8 URL Type Definition ....................................25
3.6.9 VERSION Type Definition ................................25
3.7 SECURITY TYPES ............................................25
3.7.1 CLASS Type Definition ..................................26
3.7.2 KEY Type Definition ....................................26
3.8 EXTENDED TYPES ............................................27
4. FORMAL GRAMMAR...............................................27
5. DIFFERENCES FROM VCARD V2.1..................................37
6. ACKNOWLEDGEMENTS.............................................39
7. AUTHORS' ADDRESSES...........................................39
8. SECURITY CONSIDERATIONS......................................39
9. REFERENCES...................................................40
10. FULL COPYRIGHT STATEMENT....................................42
Overview
The [MIME-DIR] document defines a MIME Content-Type for holding
different kinds of directory information. The directory information
can be based on any of a number of directory schemas. This document
defines a [MIME-DIR] usage profile for conveying directory
information based on one such schema; that of the white-pages type of
person object.
The schema is based on the attributes for the person object defined
in the X.520 and X.521 directory services recommendations. The schema
has augmented the basic attributes defined in the X.500 series
recommendation in order to provide for an electronic representation
of the information commonly found on a paper business card. This
schema was first defined in the [VCARD] document. Hence, this [MIME-
DIR] profile is referred to as the vCard MIME Directory Profile.
A directory entry based on this usage profile can include traditional
directory, white-pages information such as the distinguished name
used to uniquely identify the entry, a formatted representation of
the name used for user-interface or presentation purposes, both the
structured and presentation form of the delivery address, various
telephone numbers and organizational information associated with the
entry. In addition, traditional paper business card information such
as an image of an organizational logo or identify photograph can be
included in this person object.
The vCard MIME Directory Profile also provides support for
representing other important information about the person associated
with the directory entry. For instance, the date of birth of the
person; an audio clip describing the pronunciation of the name
associated with the directory entry, or some other application of the
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RFC 2426 vCard MIME Directory Profile September 1998
digital sound; longitude and latitude geo-positioning information
related to the person associated with the directory entry; date and
time that the directory information was last updated; annotations
often written on a business card; Uniform Resource Locators (URL) for
a website; public key information. The profile also provides support
for non-standard extensions to the schema. This provides the
flexibility for implementations to augment the current capabilities
of the profile in a standardized way. More information about this
electronic business card format can be found in [VCARD].
1. The vCard Mime Directory Profile Registration
This profile is identified by the following [MIME-DIR] registration
template information. Subsequent sections define the profile
definition.
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME profile VCARD
Profile name: VCARD
Profile purpose: To hold person object or white-pages type of
directory information. The person schema captured in the directory
entries is that commonly found in an electronic business card.
Predefined MIME Directory value specifications used: uri, date,
date-time, float
New value specifications: This profile places further constraints on
the [MIME-DIR] text value specification. In addition, it adds a
binary, phone-number, utc-offset and vcard value specifications.
Predefined MIME Directory types used: SOURCE, NAME, PROFILE, BEGIN,
END.
Predefined MIME Directory parameters used: ENCODING, VALUE, CHARSET,
LANGUAGE, CONTEXT.
New types: FN, N, NICKNAME, PHOTO, BDAY, ADR, LABEL, TEL, EMAIL,
MAILER, TZ, GEO, TITLE, ROLE, LOGO, AGENT, ORG, CATEGORIES, NOTE,
PRODID, REV, SORT-STRING, SOUND, URL, UID, VERSION, CLASS, KEY
New parameters: TYPE
Profile special notes: The vCard object MUST contain the FN, N and
VERSION types. The type-grouping feature of [MIME-DIR] is supported
by this profile to group related vCard properties about a directory
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RFC 2426 vCard MIME Directory Profile September 1998
entry. For example, vCard properties describing WORK or HOME related
characteristics can be grouped with a unique group label.
The profile permits the use of non-standard types (i.e., those
identified with the prefix string "X-") as a flexible method for
implementations to extend the functionality currently defined within
this profile.
2. MIME Directory Features
The vCard MIME Directory Profile makes use of many of the features
defined by [MIME-DIR]. The following sections either clarify or
extend the content-type definition of [MIME-DIR].
2.1 Predefined Type Usage
The vCard MIME Directory Profile uses the following predefined types
from [MIME-DIR].
2.1.1 BEGIN and END Type
The content entity MUST begin with the BEGIN type with a value of
"VCARD". The content entity MUST end with the END type with a value
of "VCARD".
2.1.2 NAME Type
If the NAME type is present, then its value is the displayable,
presentation text associated with the source for the vCard, as
specified in the SOURCE type.
2.1.3 PROFILE Type
If the PROFILE type is present, then its value MUST be "VCARD".
2.1.4 SOURCE Type
If the SOURCE type is present, then its value provides information
how to find the source for the vCard.
Dawson & Howes Standards Track [Page 5]
RFC 2426 vCard MIME Directory Profile September 1998
2.2 Predefined Type Parameter Usage
The vCard MIME Directory Profile uses the following predefined type
parameters as defined by [MIME-DIR].
- LANGUAGE
- ENCODING
- VALUE
2.3 Predefined VALUE Type Usage
The predefined data type values specified in [MIME-DIR] MUST NOT be
repeated in COMMA separated value lists except within the N,
NICKNAME, ADR and CATEGORIES value types.
The text value type defined in [MIME-DIR] is further restricted such
that any SEMI-COLON character (ASCII decimal 59) in the value MUST be
escaped with the BACKSLASH character (ASCII decimal 92).
2.4 Extensions To The Predefined VALUE Types
The predefined data type values specified in [MIME-DIR] have been
extended by the vCard profile to include a number of value types that
are specific to this profile.
2.4.1 BINARY
The "binary" value type specifies that the type value is inline,
encoded binary data. This value type can be specified in the PHOTO,
LOGO, SOUND, and KEY types.
If inline encoded binary data is specified, the ENCODING type
parameter MUST be used to specify the encoding format. The binary
data MUST be encoded using the "B" encoding format. Long lines of
encoded binary data SHOULD BE folded to 75 characters using the
folding method defined in [MIME-DIR].
The value type is defined by the following notation:
binary = <A "B" binary encoded string as defined by [RFC 2047].>
2.4.2 VCARD
The "vcard" value type specifies that the type value is another
vCard. This value type can be specified in the AGENT type. The value
type is defined by this specification. Since each of the type
Dawson & Howes Standards Track [Page 6]
RFC 2426 vCard MIME Directory Profile September 1998
declarations with in the vcard value type are being specified within
a text value themselves, they MUST be terminated with the backslash
escape sequence "\n" or "\N", instead of the normal newline character
sequence CRLF. In addition, any COMMA character (ASCII decimal 44),
SEMI-COLON character (ASCII decimal 59) and COLON character (ASCII
decimal 58) MUST be escaped with the BACKSLASH character (ASCII
decimal 92). For example, with the AGENT type a value would be
specified as:
AGENT:BEGIN:VCARD\nFN:Joe Friday\nTEL:+1-919-555-7878\n
TITLE:Area Administrator\, Assistant\n EMAIL\;TYPE=INTERN\n
ET:jfriday@host.com\nEND:VCARD\n
2.4.3 PHONE-NUMBER
The "phone-number" value type specifies that the type value is a
telephone number. This value type can be specified in the TEL type.
The value type is a text value that has the special semantics of a
telephone number as defined in [CCITT E.163] and [CCITT X.121].
2.4.4 UTC-OFFSET
The "utc-offset" value type specifies that the type value is a signed
offset from UTC. This value type can be specified in the TZ type.
The value type is an offset from Coordinated Universal Time (UTC). It
is specified as a positive or negative difference in units of hours
and minutes (e.g., +hh:mm). The time is specified as a 24-hour clock.
Hour values are from 00 to 23, and minute values are from 00 to 59.
Hour and minutes are 2-digits with high order zeroes required to
maintain digit count. The extended format for ISO 8601 UTC offsets
MUST be used. The extended format makes use of a colon character as a
separator of the hour and minute text fields.
The value is defined by the following notation:
time-hour = 2DIGIT ;00-23
time-minute = 2DIGIT ;00-59
utc-offset = ("+" / "-") time-hour ":" time-minute
2.5 Structured Type Values
Compound type values are delimited by a field delimiter, specified by
the SEMI-COLON character (ASCII decimal 59). A SEMI-COLON in a
component of a compound property value MUST be escaped with a
BACKSLASH character (ASCII decimal 92).
Dawson & Howes Standards Track [Page 7]
RFC 2426 vCard MIME Directory Profile September 1998
Lists of values are delimited by a list delimiter, specified by the
COMMA character (ASCII decimal 44). A COMMA character in a value MUST
be escaped with a BACKSLASH character (ASCII decimal 92).
This profile supports the type grouping mechanism defined in [MIME-
DIR]. Grouping of related types is a useful technique to communicate
common semantics concerning the properties of a vCard.
2.6 Line Delimiting and Folding
This profile supports the same line delimiting and folding methods
defined in [MIME-DIR]. Specifically, when parsing a content line,
folded lines must first be unfolded according to the unfolding
procedure described in [MIME-DIR]. After generating a content line,
lines longer than 75 characters SHOULD be folded according to the
folding procedure described in [MIME DIR].
Folding is done after any content encoding of a type value. Unfolding
is done before any decoding of a type value in a content line.
3. vCard Profile Features
The vCard MIME Directory Profile Type contains directory information,
typically pertaining to a single directory entry. The information is
described using an attribute schema that is tailored for capturing
personal contact information. The vCard can include attributes that
describe identification, delivery addressing, telecommunications
addressing, geographical, organizational, general explanatory and
security and access information about the particular object
associated with the vCard.
3.1 Identification Types
These types are used in the vCard profile to capture information
associated with the identification and naming of the person or
resource associated with the vCard.
3.1.1 FN Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type FN
Type name:FN
Type purpose: To specify the formatted text corresponding to the name
of the object the vCard represents.
Dawson & Howes Standards Track [Page 8]
RFC 2426 vCard MIME Directory Profile September 1998
Type encoding: 8bit
Type value: A single text value.
Type special notes: This type is based on the semantics of the X.520
Common Name attribute. The property MUST be present in the vCard
object.
Type example:
FN:Mr. John Q. Public\, Esq.
3.1.2 N Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type N
Type name: N
Type purpose: To specify the components of the name of the object the
vCard represents.
Type encoding: 8bit
Type value: A single structured text value. Each component can have
multiple values.
Type special note: The structured type value corresponds, in
sequence, to the Family Name, Given Name, Additional Names, Honorific
Prefixes, and Honorific Suffixes. The text components are separated
by the SEMI-COLON character (ASCII decimal 59). Individual text
components can include multiple text values (e.g., multiple
Additional Names) separated by the COMMA character (ASCII decimal
44). This type is based on the semantics of the X.520 individual name
attributes. The property MUST be present in the vCard object.
Type example:
N:Public;John;Quinlan;Mr.;Esq.
N:Stevenson;John;Philip,Paul;Dr.;Jr.,M.D.,A.C.P.
3.1.3 NICKNAME Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type NICKNAME
Dawson & Howes Standards Track [Page 9]
RFC 2426 vCard MIME Directory Profile September 1998
Type name: NICKNAME
Type purpose: To specify the text corresponding to the nickname of
the object the vCard represents.
Type encoding: 8bit
Type value: One or more text values separated by a COMMA character
(ASCII decimal 44).
Type special note: The nickname is the descriptive name given instead
of or in addition to the one belonging to a person, place, or thing.
It can also be used to specify a familiar form of a proper name
specified by the FN or N types.
Type example:
NICKNAME:Robbie
NICKNAME:Jim,Jimmie
3.1.4 PHOTO Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type PHOTO
Type name: PHOTO
Type purpose: To specify an image or photograph information that
annotates some aspect of the object the vCard represents.
Type encoding: The encoding MUST be reset to "b" using the ENCODING
parameter in order to specify inline, encoded binary data. If the
value is referenced by a URI value, then the default encoding of 8bit
is used and no explicit ENCODING parameter is needed.
Type value: A single value. The default is binary value. It can also
be reset to uri value. The uri value can be used to specify a value
outside of this MIME entity.
Type special notes: The type can include the type parameter "TYPE" to
specify the graphic image format type. The TYPE parameter values MUST
be one of the IANA registered image formats or a non-standard image
format.
Dawson & Howes Standards Track [Page 10]
RFC 2426 vCard MIME Directory Profile September 1998
Type example:
PHOTO;VALUE=uri:http://www.abc.com/pub/photos
/jqpublic.gif
PHOTO;ENCODING=b;TYPE=JPEG:MIICajCCAdOgAwIBAgICBEUwDQYJKoZIhvcN
AQEEBQAwdzELMAkGA1UEBhMCVVMxLDAqBgNVBAoTI05ldHNjYXBlIENvbW11bm
ljYXRpb25zIENvcnBvcmF0aW9uMRwwGgYDVQQLExNJbmZvcm1hdGlvbiBTeXN0
<...remainder of "B" encoded binary data...>
3.1.5 BDAY Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type BDAY
Type name: BDAY
Type purpose: To specify the birth date of the object the vCard
represents.
Type encoding: 8bit
Type value: The default is a single date value. It can also be reset
to a single date-time value.
Type examples:
BDAY:1996-04-15
BDAY:1953-10-15T23:10:00Z
BDAY:1987-09-27T08:30:00-06:00
3.2 Delivery Addressing Types
These types are concerned with information related to the delivery
addressing or label for the vCard object.
3.2.1 ADR Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type ADR
Type name: ADR
Dawson & Howes Standards Track [Page 11]
RFC 2426 vCard MIME Directory Profile September 1998
Type purpose: To specify the components of the delivery address for
the vCard object.
Type encoding: 8bit
Type value: A single structured text value, separated by the
SEMI-COLON character (ASCII decimal 59).
Type special notes: The structured type value consists of a sequence
of address components. The component values MUST be specified in
their corresponding position. The structured type value corresponds,
in sequence, to the post office box; the extended address; the street
address; the locality (e.g., city); the region (e.g., state or
province); the postal code; the country name. When a component value
is missing, the associated component separator MUST still be
specified.
The text components are separated by the SEMI-COLON character (ASCII
decimal 59). Where it makes semantic sense, individual text
components can include multiple text values (e.g., a "street"
component with multiple lines) separated by the COMMA character
(ASCII decimal 44).
The type can include the type parameter "TYPE" to specify the
delivery address type. The TYPE parameter values can include "dom" to
indicate a domestic delivery address; "intl" to indicate an
international delivery address; "postal" to indicate a postal
delivery address; "parcel" to indicate a parcel delivery address;
"home" to indicate a delivery address for a residence; "work" to
indicate delivery address for a place of work; and "pref" to indicate
the preferred delivery address when more than one address is
specified. These type parameter values can be specified as a
parameter list (i.e., "TYPE=dom;TYPE=postal") or as a value list
(i.e., "TYPE=dom,postal"). This type is based on semantics of the
X.520 geographical and postal addressing attributes. The default is
"TYPE=intl,postal,parcel,work". The default can be overridden to some
other set of values by specifying one or more alternate values. For
example, the default can be reset to "TYPE=dom,postal,work,home" to
specify a domestic delivery address for postal delivery to a
residence that is also used for work.
Type example: In this example the post office box and the extended
address are absent.
ADR;TYPE=dom,home,postal,parcel:;;123 Main
Street;Any Town;CA;91921-1234
Dawson & Howes Standards Track [Page 12]
RFC 2426 vCard MIME Directory Profile September 1998
3.2.2 LABEL Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type LABEL
Type name: LABEL
Type purpose: To specify the formatted text corresponding to delivery
address of the object the vCard represents.
Type encoding: 8bit
Type value: A single text value.
Type special notes: The type value is formatted text that can be used
to present a delivery address label for the vCard object. The type
can include the type parameter "TYPE" to specify delivery label type.
The TYPE parameter values can include "dom" to indicate a domestic
delivery label; "intl" to indicate an international delivery label;
"postal" to indicate a postal delivery label; "parcel" to indicate a
parcel delivery label; "home" to indicate a delivery label for a
residence; "work" to indicate delivery label for a place of work; and
"pref" to indicate the preferred delivery label when more than one
label is specified. These type parameter values can be specified as a
parameter list (i.e., "TYPE=dom;TYPE=postal") or as a value list
(i.e., "TYPE=dom,postal"). This type is based on semantics of the
X.520 geographical and postal addressing attributes. The default is
"TYPE=intl,postal,parcel,work". The default can be overridden to some
other set of values by specifying one or more alternate values. For
example, the default can be reset to "TYPE=intl,post,parcel,home" to
specify an international delivery label for both postal and parcel
delivery to a residential location.
Type example: A multi-line address label.
LABEL;TYPE=dom,home,postal,parcel:Mr.John Q. Public\, Esq.\n
Mail Drop: TNE QB\n123 Main Street\nAny Town\, CA 91921-1234
\nU.S.A.
3.3 Telecommunications Addressing Types
These types are concerned with information associated with the
telecommunications addressing of the object the vCard represents.
Dawson & Howes Standards Track [Page 13]
RFC 2426 vCard MIME Directory Profile September 1998
3.3.1 TEL Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type TEL
Type name: TEL
Type purpose: To specify the telephone number for telephony
communication with the object the vCard represents.
Type encoding: 8bit
Type value: A single phone-number value.
Type special notes: The value of this type is specified in a
canonical form in order to specify an unambiguous representation of
the globally unique telephone endpoint. This type is based on the
X.500 Telephone Number attribute.
The type can include the type parameter "TYPE" to specify intended
use for the telephone number. The TYPE parameter values can include:
"home" to indicate a telephone number associated with a residence,
"msg" to indicate the telephone number has voice messaging support,
"work" to indicate a telephone number associated with a place of
work, "pref" to indicate a preferred-use telephone number, "voice" to
indicate a voice telephone number, "fax" to indicate a facsimile
telephone number, "cell" to indicate a cellular telephone number,
"video" to indicate a video conferencing telephone number, "pager" to
indicate a paging device telephone number, "bbs" to indicate a
bulletin board system telephone number, "modem" to indicate a MODEM
connected telephone number, "car" to indicate a car-phone telephone
number, "isdn" to indicate an ISDN service telephone number, "pcs" to
indicate a personal communication services telephone number. The
default type is "voice". These type parameter values can be specified
as a parameter list (i.e., "TYPE=work;TYPE=voice") or as a value list
(i.e., "TYPE=work,voice"). The default can be overridden to another
set of values by specifying one or more alternate values. For
example, the default TYPE of "voice" can be reset to a WORK and HOME,
VOICE and FAX telephone number by the value list
"TYPE=work,home,voice,fax".
Type example:
TEL;TYPE=work,voice,pref,msg:+1-213-555-1234
Dawson & Howes Standards Track [Page 14]
RFC 2426 vCard MIME Directory Profile September 1998
3.3.2 EMAIL Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type EMAIL
Type name: EMAIL
Type purpose: To specify the electronic mail address for
communication with the object the vCard represents.
Type encoding: 8bit
Type value: A single text value.
Type special notes: The type can include the type parameter "TYPE" to
specify the format or preference of the electronic mail address. The
TYPE parameter values can include: "internet" to indicate an Internet
addressing type, "x400" to indicate a X.400 addressing type or "pref"
to indicate a preferred-use email address when more than one is
specified. Another IANA registered address type can also be
specified. The default email type is "internet". A non-standard value
can also be specified.
Type example:
EMAIL;TYPE=internet:jqpublic@xyz.dom1.com
EMAIL;TYPE=internet:jdoe@isp.net
EMAIL;TYPE=internet,pref:jane_doe@abc.com
3.3.3 MAILER Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type MAILER
Type name: MAILER
Type purpose: To specify the type of electronic mail software that is
used by the individual associated with the vCard.
Type encoding: 8bit
Type value: A single text value.
Dawson & Howes Standards Track [Page 15]
RFC 2426 vCard MIME Directory Profile September 1998
Type special notes: This information can provide assistance to a
correspondent regarding the type of data representation which can be
used, and how they can be packaged. This property is based on the
private MIME type X-Mailer that is generally implemented by MIME user
agent products.
Type example:
MAILER:PigeonMail 2.1
3.4 Geographical Types
These types are concerned with information associated with
geographical positions or regions associated with the object the
vCard represents.
3.4.1 TZ Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type TZ
Type name: TZ
Type purpose: To specify information related to the time zone of the
object the vCard represents.
Type encoding: 8bit
Type value: The default is a single utc-offset value. It can also be
reset to a single text value.
Type special notes: The type value consists of a single value.
Type examples:
TZ:-05:00
TZ;VALUE=text:-05:00; EST; Raleigh/North America
;This example has a single value, not a structure text value.
3.4.2 GEO Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type GEO
Type name: GEO
Dawson & Howes Standards Track [Page 16]
RFC 2426 vCard MIME Directory Profile September 1998
Type purpose: To specify information related to the global
positioning of the object the vCard represents.
Type encoding: 8bit
Type value: A single structured value consisting of two float values
separated by the SEMI-COLON character (ASCII decimal 59).
Type special notes: This type specifies information related to the
global position of the object associated with the vCard. The value
specifies latitude and longitude, in that order (i.e., "LAT LON"
ordering). The longitude represents the location east and west of the
prime meridian as a positive or negative real number, respectively.
The latitude represents the location north and south of the equator
as a positive or negative real number, respectively. The longitude
and latitude values MUST be specified as decimal degrees and should
be specified to six decimal places. This will allow for granularity
within a meter of the geographical position. The text components are
separated by the SEMI-COLON character (ASCII decimal 59). The simple
formula for converting degrees-minutes-seconds into decimal degrees
is:
decimal = degrees + minutes/60 + seconds/3600.
Type example:
GEO:37.386013;-122.082932
3.5 Organizational Types
These types are concerned with information associated with
characteristics of the organization or organizational units of the
object the vCard represents.
3.5.1 TITLE Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type TITLE
Type name: TITLE
Type purpose: To specify the job title, functional position or
function of the object the vCard represents.
Type encoding: 8bit
Type value: A single text value.
Dawson & Howes Standards Track [Page 17]
RFC 2426 vCard MIME Directory Profile September 1998
Type special notes: This type is based on the X.520 Title attribute.
Type example:
TITLE:Director\, Research and Development
3.5.2 ROLE Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type ROLE
Type name: ROLE
Type purpose: To specify information concerning the role, occupation,
or business category of the object the vCard represents.
Type encoding: 8bit
Type value: A single text value.
Type special notes: This type is based on the X.520 Business Category
explanatory attribute. This property is included as an organizational
type to avoid confusion with the semantics of the TITLE type and
incorrect usage of that type when the semantics of this type is
intended.
Type example:
ROLE:Programmer
3.5.3 LOGO Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type LOGO
Type name: LOGO
Type purpose: To specify a graphic image of a logo associated with
the object the vCard represents.
Type encoding: The encoding MUST be reset to "b" using the ENCODING
parameter in order to specify inline, encoded binary data. If the
value is referenced by a URI value, then the default encoding of 8bit
is used and no explicit ENCODING parameter is needed.
Dawson & Howes Standards Track [Page 18]
RFC 2426 vCard MIME Directory Profile September 1998
Type value: A single value. The default is binary value. It can also
be reset to uri value. The uri value can be used to specify a value
outside of this MIME entity.
Type special notes: The type can include the type parameter "TYPE" to
specify the graphic image format type. The TYPE parameter values MUST
be one of the IANA registered image formats or a non-standard image
format.
Type example:
LOGO;VALUE=uri:http://www.abc.com/pub/logos/abccorp.jpg
LOGO;ENCODING=b;TYPE=JPEG:MIICajCCAdOgAwIBAgICBEUwDQYJKoZIhvcN
AQEEBQAwdzELMAkGA1UEBhMCVVMxLDAqBgNVBAoTI05ldHNjYXBlIENvbW11bm
ljYXRpb25zIENvcnBvcmF0aW9uMRwwGgYDVQQLExNJbmZvcm1hdGlvbiBTeXN0
<...the remainder of "B" encoded binary data...>
3.5.4 AGENT Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type AGENT
Type name: AGENT
Type purpose: To specify information about another person who will
act on behalf of the individual or resource associated with the
vCard.
Type encoding: 8-bit
Type value: The default is a single vcard value. It can also be reset
to either a single text or uri value. The text value can be used to
specify textual information. The uri value can be used to specify
information outside of this MIME entity.
Type special notes: This type typically is used to specify an area
administrator, assistant, or secretary for the individual associated
with the vCard. A key characteristic of the Agent type is that it
represents somebody or something that is separately addressable.
Type example:
AGENT;VALUE=uri:
CID:JQPUBLIC.part3.960129T083020.xyzMail@host3.com
Dawson & Howes Standards Track [Page 19]
RFC 2426 vCard MIME Directory Profile September 1998
AGENT:BEGIN:VCARD\nFN:Susan Thomas\nTEL:+1-919-555-
1234\nEMAIL\;INTERNET:sthomas@host.com\nEND:VCARD\n
3.5.5 ORG Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type ORG
Type name: ORG
Type purpose: To specify the organizational name and units associated
with the vCard.
Type encoding: 8bit
Type value: A single structured text value consisting of components
separated the SEMI-COLON character (ASCII decimal 59).
Type special notes: The type is based on the X.520 Organization Name
and Organization Unit attributes. The type value is a structured type
consisting of the organization name, followed by one or more levels
of organizational unit names.
Type example: A type value consisting of an organizational name,
organizational unit #1 name and organizational unit #2 name.
ORG:ABC\, Inc.;North American Division;Marketing
3.6 Explanatory Types
These types are concerned with additional explanations, such as that
related to informational notes or revisions specific to the vCard.
3.6.1 CATEGORIES Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type CATEGORIES
Type name: CATEGORIES
Type purpose: To specify application category information about the
vCard.
Type encoding: 8bit
Dawson & Howes Standards Track [Page 20]
RFC 2426 vCard MIME Directory Profile September 1998
Type value: One or more text values separated by a COMMA character
(ASCII decimal 44).
Type example:
CATEGORIES:TRAVEL AGENT
CATEGORIES:INTERNET,IETF,INDUSTRY,INFORMATION TECHNOLOGY
3.6.2 NOTE Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type NOTE
Type name: NOTE
Type purpose: To specify supplemental information or a comment that
is associated with the vCard.
Type encoding: 8bit
Type value: A single text value.
Type special notes: The type is based on the X.520 Description
attribute.
Type example:
NOTE:This fax number is operational 0800 to 1715
EST\, Mon-Fri.
3.6.3 PRODID Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type PRODID
Type name: PRODID
Type purpose: To specify the identifier for the product that created
the vCard object.
Type encoding: 8-bit
Type value: A single text value.
Dawson & Howes Standards Track [Page 21]
RFC 2426 vCard MIME Directory Profile September 1998
Type special notes: Implementations SHOULD use a method such as that
specified for Formal Public Identifiers in ISO 9070 to assure that
the text value is unique.
Type example:
PRODID:-//ONLINE DIRECTORY//NONSGML Version 1//EN
3.6.4 REV Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type REV
Type name: REV
Type purpose: To specify revision information about the current
vCard.
Type encoding: 8-bit
Type value: The default is a single date-time value. Can also be
reset to a single date value.
Type special notes: The value distinguishes the current revision of
the information in this vCard for other renditions of the
information.
Type example:
REV:1995-10-31T22:27:10Z
REV:1997-11-15
3.6.5 SORT-STRING Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type SORT-STRING
Type Name: SORT-STRING
Type purpose: To specify the family name or given name text to be
used for national-language-specific sorting of the FN and N types.
Type encoding: 8bit
Type value: A single text value.
Dawson & Howes Standards Track [Page 22]
RFC 2426 vCard MIME Directory Profile September 1998
Type special notes: The sort string is used to provide family name or
given name text that is to be used in locale- or national-language-
specific sorting of the formatted name and structured name types.
Without this information, sorting algorithms could incorrectly sort
this vCard within a sequence of sorted vCards. When this type is
present in a vCard, then this family name or given name value is used
for sorting the vCard.
Type examples: For the case of family name sorting, the following
examples define common sort string usage with the FN and N types.
FN:Rene van der Harten
N:van der Harten;Rene;J.;Sir;R.D.O.N.
SORT-STRING:Harten
FN:Robert Pau Shou Chang
N:Pau;Shou Chang;Robert
SORT-STRING:Pau
FN:Osamu Koura
N:Koura;Osamu
SORT-STRING:Koura
FN:Oscar del Pozo
N:del Pozo Triscon;Oscar
SORT-STRING:Pozo
FN:Chistine d'Aboville
N:d'Aboville;Christine
SORT-STRING:Aboville
3.6.6 SOUND Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type SOUND
Type name: SOUND
Type purpose: To specify a digital sound content information that
annotates some aspect of the vCard. By default this type is used to
specify the proper pronunciation of the name type value of the vCard.
Type encoding: The encoding MUST be reset to "b" using the ENCODING
parameter in order to specify inline, encoded binary data. If the
value is referenced by a URI value, then the default encoding of 8bit
is used and no explicit ENCODING parameter is needed.
Dawson & Howes Standards Track [Page 23]
RFC 2426 vCard MIME Directory Profile September 1998
Type value: A single value. The default is binary value. It can also
be reset to uri value. The uri value can be used to specify a value
outside of this MIME entity.
Type special notes: The type can include the type parameter "TYPE" to
specify the audio format type. The TYPE parameter values MUST be one
of the IANA registered audio formats or a non-standard audio format.
Type example:
SOUND;TYPE=BASIC;VALUE=uri:CID:JOHNQPUBLIC.part8.
19960229T080000.xyzMail@host1.com
SOUND;TYPE=BASIC;ENCODING=b:MIICajCCAdOgAwIBAgICBEUwDQYJKoZIhvcN
AQEEBQAwdzELMAkGA1UEBhMCVVMxLDAqBgNVBAoTI05ldHNjYXBlIENvbW11bm
ljYXRpb25zIENvcnBvcmF0aW9uMRwwGgYDVQQLExNJbmZvcm1hdGlvbiBTeXN0
<...the remainder of "B" encoded binary data...>
3.6.7 UID Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type UID
Type name: UID
Type purpose: To specify a value that represents a globally unique
identifier corresponding to the individual or resource associated
with the vCard.
Type encoding: 8bit
Type value: A single text value.
Type special notes: The type is used to uniquely identify the object
that the vCard represents.
The type can include the type parameter "TYPE" to specify the format
of the identifier. The TYPE parameter value should be an IANA
registered identifier format. The value can also be a non-standard
format.
Type example:
UID:19950401-080045-40000F192713-0052
Dawson & Howes Standards Track [Page 24]
RFC 2426 vCard MIME Directory Profile September 1998
3.6.8 URL Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type URL
Type name: URL
Type purpose: To specify a uniform resource locator associated with
the object that the vCard refers to.
Type encoding: 8bit
Type value: A single uri value.
Type example:
URL:http://www.swbyps.restaurant.french/~chezchic.html
3.6.9 VERSION Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type VERSION
Type name: VERSION
Type purpose: To specify the version of the vCard specification used
to format this vCard.
Type encoding: 8bit
Type value: A single text value.
Type special notes: The property MUST be present in the vCard object.
The value MUST be "3.0" if the vCard corresponds to this
specification.
Type example:
VERSION:3.0
3.7 Security Types
These types are concerned with the security of communication pathways
or access to the vCard.
Dawson & Howes Standards Track [Page 25]
RFC 2426 vCard MIME Directory Profile September 1998
3.7.1 CLASS Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type CLASS
Type name: CLASS
Type purpose: To specify the access classification for a vCard
object.
Type encoding: 8bit
Type value: A single text value.
Type special notes: An access classification is only one component of
the general security model for a directory service. The
classification attribute provides a method of capturing the intent of
the owner for general access to information described by the vCard
object.
Type examples:
CLASS:PUBLIC
CLASS:PRIVATE
CLASS:CONFIDENTIAL
3.7.2 KEY Type Definition
To: ietf-mime-directory@imc.org
Subject: Registration of text/directory MIME type KEY
Type name: KEY
Type purpose: To specify a public key or authentication certificate
associated with the object that the vCard represents.
Type encoding: The encoding MUST be reset to "b" using the ENCODING
parameter in order to specify inline, encoded binary data. If the
value is a text value, then the default encoding of 8bit is used and
no explicit ENCODING parameter is needed.
Type value: A single value. The default is binary. It can also be
reset to text value. The text value can be used to specify a text
key.
Dawson & Howes Standards Track [Page 26]
RFC 2426 vCard MIME Directory Profile September 1998
Type special notes: The type can also include the type parameter TYPE
to specify the public key or authentication certificate format. The
parameter type should specify an IANA registered public key or
authentication certificate format. The parameter type can also
specify a non-standard format.
Type example:
KEY;ENCODING=b:MIICajCCAdOgAwIBAgICBEUwDQYJKoZIhvcNAQEEBQA
wdzELMAkGA1UEBhMCVVMxLDAqBgNVBAoTI05ldHNjYXBlIENbW11bmljYX
Rpb25zIENvcnBvcmF0aW9uMRwwGgYDVQQLExNJbmZvcm1hdGlvbiBTeXN0
ZW1zMRwwGgYDVQQDExNyb290Y2EubmV0c2NhcGUuY29tMB4XDTk3MDYwNj
E5NDc1OVoXDTk3MTIwMzE5NDc1OVowgYkxCzAJBgNVBAYTAlVTMSYwJAYD
VQQKEx1OZXRzY2FwZSBDb21tdW5pY2F0aW9ucyBDb3JwLjEYMBYGA1UEAx
MPVGltb3RoeSBBIEhvd2VzMSEwHwYJKoZIhvcNAQkBFhJob3dlc0BuZXRz
Y2FwZS5jb20xFTATBgoJkiaJk/IsZAEBEwVob3dlczBcMA0GCSqGSIb3DQ
EBAQUAA0sAMEgCQQC0JZf6wkg8pLMXHHCUvMfL5H6zjSk4vTTXZpYyrdN2
dXcoX49LKiOmgeJSzoiFKHtLOIboyludF90CgqcxtwKnAgMBAAGjNjA0MB
EGCWCGSAGG+EIBAQQEAwIAoDAfBgNVHSMEGDAWgBT84FToB/GV3jr3mcau
+hUMbsQukjANBgkqhkiG9w0BAQQFAAOBgQBexv7o7mi3PLXadkmNP9LcIP
mx93HGp0Kgyx1jIVMyNgsemeAwBM+MSlhMfcpbTrONwNjZYW8vJDSoi//y
rZlVt9bJbs7MNYZVsyF1unsqaln4/vy6Uawfg8VUMk1U7jt8LYpo4YULU7
UZHPYVUaSgVttImOHZIKi4hlPXBOhcUQ==
3.8 Extended Types
The types defined by this document can be extended with private types
using the non-standard, private values mechanism defined in [RFC
2045]. Non-standard, private types with a name starting with "X-" may
be defined bilaterally between two cooperating agents without outside
registration or standardization.
4. Formal Grammar
The following formal grammar is provided to assist developers in
building parsers for the vCard.
This syntax is written according to the form described in RFC 2234,
but it references just this small subset of RFC 2234 literals:
;*******************************************
; Commonly Used Literal Definition
;*******************************************
ALPHA = %x41-5A / %x61-7A
; Latin Capital Letter A-Latin Capital Letter Z /
; Latin Small Letter a-Latin Small Letter z
Dawson & Howes Standards Track [Page 27]
RFC 2426 vCard MIME Directory Profile September 1998
CHAR = %x01-7F
; Any C0 Controls and Basic Latin, excluding NULL from
; Code Charts, pages 7-6 through 7-9 in [UNICODE]
CR = %x0D
; Carriage Return
LF = %0A
; Line Feed
CRLF = CR LF
; Internet standard newline
;CTL = %x00-1F / %x7F
; Controls. Not used, but referenced in comments.
DIGIT = %x30-39
; Digit Zero-Digit Nine
DQUOTE = %x22
; Quotation Mark
HTAB = %x09
; Horizontal Tabulation
SP = %x20
; space
VCHAR = %x21-7E
; Visible (printing) characters
WSP = SP / HTAB
; White Space
;*******************************************
; Basic vCard Definition
;*******************************************
vcard_entity = 1*(vcard)
vcard = [group "."] "BEGIN" ":" "VCARD" 1*CRLF
1*(contentline)
;A vCard object MUST include the VERSION, FN and N types.
[group "."] "END" ":" "VCARD" 1*CRLF
contentline = [group "."] name *(";" param ) ":" value CRLF
; When parsing a content line, folded lines must first
; be unfolded according to the unfolding procedure
Dawson & Howes Standards Track [Page 28]
RFC 2426 vCard MIME Directory Profile September 1998
; described above. When generating a content line, lines
; longer than 75 characters SHOULD be folded according to
; the folding procedure described in [MIME DIR].
group = 1*(ALPHA / DIGIT / "-")
name = iana-token / x-name
; Parsing of the param and value is
; based on the "name" or type identifier
; as defined in ABNF sections below
iana-token = 1*(ALPHA / DIGIT / "-")
; vCard type or parameter identifier registered with IANA
x-name = "X-" 1*(ALPHA / DIGIT / "-")
; Reserved for non-standard use
param = param-name "=" param-value *("," param-value)
param-name = iana-token / x-name
param-value = ptext / quoted-string
ptext = *SAFE-CHAR
value = *VALUE-CHAR
quoted-string = DQUOTE QSAFE-CHAR DQUOTE
NON-ASCII = %x80-FF
; Use is restricted by CHARSET parameter
; on outer MIME object (UTF-8 preferred)
QSAFE-CHAR = WSP / %x21 / %x23-7E / NON-ASCII
; Any character except CTLs, DQUOTE
SAFE-CHAR = WSP / %x21 / %x23-2B / %x2D-39 / %x3C-7E / NON-ASCII
; Any character except CTLs, DQUOTE, ";", ":", ","
VALUE-CHAR = WSP / VCHAR / NON-ASCII
; Any textual character
;*******************************************
; vCard Type Definition
;
; Provides type-specific definitions for how the
; "value" and "param" are defined.
;*******************************************
Dawson & Howes Standards Track [Page 29]
RFC 2426 vCard MIME Directory Profile September 1998
;For name="NAME"
param = ""
; No parameters allowed
value = text-value
;For name="PROFILE"
param = ""
; No parameters allowed
value = text-value
; Value MUST be the case insensitive value "VCARD
;For name="SOURCE"
param = source-param
; No parameters allowed
value = uri
source-param = ("VALUE" "=" "uri")
/ ("CONTEXT" "=" "word")
; Parameter value specifies the protocol context
; for the uri value.
/ (x-name "=" *SAFE-CHAR)
;For name="FN"
;This type MUST be included in a vCard object.
param = text-param
; Text parameters allowed
value = text-value
;For name="N"
;This type MUST be included in a vCard object.
param = text-param
; Text parameters allowed
value = n-value
n-value = 0*4(text-value *("," text-value) ";")
text-value *("," text-value)
; Family; Given; Middle; Prefix; Suffix.
; Example: Public;John;Quincy,Adams;Reverend Dr. III
;For name="NICKNAME"
param = text-param
; Text parameters allowed
Dawson & Howes Standards Track [Page 30]
RFC 2426 vCard MIME Directory Profile September 1998
value = text-list
;For name="PHOTO"
param = img-inline-param
; Only image parameters allowed
param =/ img-refer-param
; Only image parameters allowed
value = img-inline-value
; Value and parameter MUST match
value =/ img-refer-value
; Value and parameter MUST match
;For name="BDAY"
param = ("VALUE" "=" "date")
; Only value parameter allowed
param =/ ("VALUE" "=" "date-time")
; Only value parameter allowed
value = date-value
; Value MUST match value type
value =/ date-time-value
; Value MUST match value type
;For name="ADR"
param = adr-param / text-param
; Only adr and text parameters allowed
value = adr-value
;For name="LABEL"
param = adr-param / text-param
; Only adr and text parameters allowed
value = text-value
;For name="TEL"
param = tel-param
; Only tel parameters allowed
value = phone-number-value
tel-param = "TYPE" "=" tel-type *("," tel-type)
Dawson & Howes Standards Track [Page 31]
RFC 2426 vCard MIME Directory Profile September 1998
tel-type = "HOME" / "WORK" / "PREF" / "VOICE" / "FAX" / "MSG"
/ "CELL" / "PAGER" / "BBS" / "MODEM" / "CAR" / "ISDN"
/ "VIDEO" / "PCS" / iana-token / x-name
; Values are case insensitive
;For name="EMAIL"
param = email-param
; Only email parameters allowed
value = text-value
email-param = "TYPE" "=" email-type ["," "PREF"]
; Value is case insensitive
email-type = "INTERNET" / "X400" / iana-token / "X-" word
; Values are case insensitive
;For name="MAILER"
param = text-param
; Only text parameters allowed
value = text-value
;For name="TZ"
param = ""
; No parameters allowed
value = utc-offset-value
;For name="GEO"
param = ""
; No parameters allowed
value = float-value ";" float-value
;For name="TITLE"
param = text-param
; Only text parameters allowed
value = text-value
;For name="ROLE"
param = text-param
; Only text parameters allowed
value = text-value
;For name="LOGO"
Dawson & Howes Standards Track [Page 32]
RFC 2426 vCard MIME Directory Profile September 1998
param = img-inline-param / img-refer-param
; Only image parameters allowed
value = img-inline-value / img-refer-value
; Value and parameter MUST match
;For name="AGENT"
param = agent-inline-param
param =/ agent-refer-param
value = agent-inline-value
; Value and parameter MUST match
value =/ agent-refer-value
; Value and parameter MUST match
agent-inline-param = ""
; No parameters allowed
agent-refer-param = "VALUE" "=" "uri"
; Only value parameter allowed
agent-inline-value = text-value
; Value MUST be a valid vCard object
agent-refer-value = uri
; URI MUST refer to image content of given type
;For name="ORG"
param = text-param
; Only text parameters allowed
value = org-value
org-value = *(text-value ";") text-value
; First is Organization Name, remainder are Organization Units.
;For name="CATEGORIES"
param = text-param
; Only text parameters allowed
value = text-list
;For name="NOTE"
param = text-param
; Only text parameters allowed
Dawson & Howes Standards Track [Page 33]
RFC 2426 vCard MIME Directory Profile September 1998
value = text-value
;For name="PRODID"
param = ""
; No parameters allowed
value = text-value
;For name="REV"
param = ["VALUE" =" "date-time"]
; Only value parameters allowed. Values are case insensitive.
param =/ "VALUE" =" "date"
; Only value parameters allowed. Values are case insensitive.
value = date-time-value
value =/ date-value
;For name="SORT-STRING"
param = text-param
; Only text parameters allowed
value = text-value
;For name="SOUND"
param = snd-inline-param
; Only sound parameters allowed
param =/ snd-refer-param
; Only sound parameters allowed
value = snd-line-value
; Value MUST match value type
value =/ snd-refer-value
; Value MUST match value type
snd-inline-value = binary-value CRLF
; Value MUST be "b" encoded audio content
snd-inline-param = ("VALUE" "=" "binary"])
/ ("ENCODING" "=" "b")
/ ("TYPE" "=" *SAFE-CHAR)
; Value MUST be an IANA registered audio type
snd-refer-value = uri
; URI MUST refer to audio content of given type
Dawson & Howes Standards Track [Page 34]
RFC 2426 vCard MIME Directory Profile September 1998
snd-refer-param = ("VALUE" "=" "uri")
/ ("TYPE" "=" word)
; Value MUST be an IANA registered audio type
;For name="UID"
param = ""
; No parameters allowed
value = text-value
;For name="URL"
param = ""
; No parameters allowed
value = uri
;For name="VERSION"
;This type MUST be included in a vCard object.
param = ""
; No parameters allowed
value = text-value
; Value MUST be "3.0"
;For name="CLASS"
param = ""
; No parameters allowed
value = "PUBLIC" / "PRIVATE" / "CONFIDENTIAL"
/ iana-token / x-name
; Value are case insensitive
;For name="KEY"
param = key-txt-param
; Only value and type parameters allowed
param =/ key-bin-param
; Only value and type parameters allowed
value = text-value
value =/ binary-value
key-txt-param = "TYPE" "=" keytype
key-bin-param = ("TYPE" "=" keytype)
/ ("ENCODING" "=" "b")
; Value MUST be a "b" encoded key or certificate
Dawson & Howes Standards Track [Page 35]
RFC 2426 vCard MIME Directory Profile September 1998
keytype = "X509" / "PGP" / iana-token / x-name
; Values are case insensitive
;For name="X-" non-standard type
param = text-param / (x-name "=" param-value)
; Only text or non-standard parameters allowed
value = text-value
;*******************************************
; vCard Commonly Used Parameter Definition
;*******************************************
text-param = ("VALUE" "=" "ptext")
/ ("LANGUAGE" "=" langval)
/ (x-name "=" param-value)
langval = <a language string as defined in RFC 1766>
img-inline-value = binary-value
;Value MUST be "b" encoded image content
img-inline-param
img-inline-param = ("VALUE" "=" "binary")
/ ("ENCODING" "=" "b")
/ ("TYPE" "=" param-value
;TYPE value MUST be an IANA registered image type
img-refer-value = uri
;URI MUST refer to image content of given type
img-refer-param = ("VALUE" "=" "uri")
/ ("TYPE" "=" param-value)
;TYPE value MUST be an IANA registered image type
adr-param = ("TYPE" "=" adr-type *("," adr-type))
/ (text-param)
adr-type = "dom" / "intl" / "postal" / "parcel" / "home"
/ "work" / "pref" / iana-type / x-name
adr-value = 0*6(text-value ";") text-value
; PO Box, Extended Address, Street, Locality, Region, Postal
; Code, Country Name
Dawson & Howes Standards Track [Page 36]
RFC 2426 vCard MIME Directory Profile September 1998
;*******************************************
; vCard Type Value Definition
;*******************************************
text-value-list = 1*text-value *("," 1*text-value)
text-value = *(SAFE-CHAR / ":" / DQUOTE / ESCAPED-CHAR)
ESCAPED-CHAR = "\\" / "\;" / "\," / "\n" / "\N")
; \\ encodes \, \n or \N encodes newline
; \; encodes ;, \, encodes ,
binary-value = <A "b" encoded text value as defined in [RFC 2047]>
date-value = <A single date value as defined in [MIME-DIR]>
time-value = <A single time value as defined in [MIME-DIR]>
date-time-value = <A single date-time value as defined in [MIME-DIR]
float-value = <A single float value as defined in [MIME-DIR]>
phone-number-value = <A single text value as defined in [CCITT
E.163] and [CCITT X.121]>
uri-value = <A uri value as defined in [MIME-DIR]>
utc-offset-value = ("+" / "-") time-hour ":" time-minute
time-hour = 2DIGIT ;00-23
time-minute = 2DIGIT ;00-59
5. Differences From vCard v2.1
This specification has been reviewed by the IETF community. The
review process introduced a number of differences from the [VCARD]
version 2.1. These differences require that vCard objects conforming
to this specification have a different version number than a vCard
conforming to [VCARD]. The differences include the following:
. The QUOTED-PRINTABLE inline encoding has been eliminated.
Only the "B" encoding of [RFC 2047] is an allowed value for
the ENCODING parameter.
. The method for specifying CRLF character sequences in text
type values has been changed. The CRLF character sequence in
a text type value is specified with the backslash character
sequence "\n" or "\N".
Dawson & Howes Standards Track [Page 37]
RFC 2426 vCard MIME Directory Profile September 1998
. Any COMMA or SEMICOLON in a text type value must be backslash
escaped.
. VERSION value corresponding to this specification MUST be
"3.0".
. The [MIME-DIR] predefined types of SOURCE, NAME and PROFILE
are allowed.
. The [MIME-DIR] VALUE type parameter for value data typing is
allowed. In addition, there are extensions made to these type
values for additional value types used in this specification.
. The [VCARD] CHARSET type parameter has been eliminated.
Character set can only be specified on the CHARSET parameter
on the Content-Type MIME header field.
. The [VCARD] support for non-significant WSP character has
been eliminated.
. The "TYPE=" prefix to parameter values is required. In
[VCARD] this was optional.
. LOGO, PHOTO and SOUND multimedia formats MUST be either IANA
registered types or non-standard types.
. Inline binary content must be "B" encoded and folded. A blank
line after the encoded binary content is no longer required.
. TEL values can be identified as personal communication
services telephone numbers with the PCS type parameter value.
. The CATEGORIES, CLASS, NICKNAME, PRODID and SORT-STRING types
have been added.
. The VERSION, N and FN types MUST be specified in a vCard.
This identifies the version of the specification that the
object was formatted to. It also assures that every vCard
will include both a structured and formatted name that can be
used to identify the object.
Dawson & Howes Standards Track [Page 38]
RFC 2426 vCard MIME Directory Profile September 1998
6. Acknowledgements
The many valuable comments contributed by members of the IETF ASID
working group are gratefully acknowledged, as are the contributions
by Roland Alden, Stephen Bartlett, Alec Dun, Patrik Faltstrom, Daniel
Gurney, Bruce Johnston, Daniel Klaussen, Pete Miller, Keith Moore,
Vinod Seraphin, Michelle Watkins. Chris Newman was especially helpful
in navigating the intricacies of ABNF lore.
7. Authors' Addresses
BEGIN:vCard
VERSION:3.0
FN:Frank Dawson
ORG:Lotus Development Corporation
ADR;TYPE=WORK,POSTAL,PARCEL:;;6544 Battleford Drive
;Raleigh;NC;27613-3502;U.S.A.
TEL;TYPE=VOICE,MSG,WORK:+1-919-676-9515
TEL;TYPE=FAX,WORK:+1-919-676-9564
EMAIL;TYPE=INTERNET,PREF:Frank_Dawson@Lotus.com
EMAIL;TYPE=INTERNET:fdawson@earthlink.net
URL:http://home.earthlink.net/~fdawson
END:vCard
BEGIN:vCard
VERSION:3.0
FN:Tim Howes
ORG:Netscape Communications Corp.
ADR;TYPE=WORK:;;501 E. Middlefield Rd.;Mountain View;
CA; 94043;U.S.A.
TEL;TYPE=VOICE,MSG,WORK:+1-415-937-3419
TEL;TYPE=FAX,WORK:+1-415-528-4164
EMAIL;TYPE=INTERNET:howes@netscape.com
END:vCard
8. Security Considerations
vCards can carry cryptographic keys or certificates, as described in
Section 3.7.2.
Section 3.7.1 specifies a desired security classification policy for
a particular vCard. That policy is not enforced in any way.
The vCard objects have no inherent authentication or privacy, but can
easily be carried by any security mechanism that transfers MIME
objects with authentication or privacy. In cases where threats of
"spoofed" vCard information is a concern, the vCard SHOULD BE
Dawson & Howes Standards Track [Page 39]
RFC 2426 vCard MIME Directory Profile September 1998
transported using one of these secure mechanisms.
The information in a vCard may become out of date. In cases where the
vitality of data is important to an originator of a vCard, the "URL"
type described in section 3.6.8 SHOULD BE specified. In addition, the
"REV" type described in section 3.6.4 can be specified to indicate
the last time that the vCard data was updated.
9. References
[ISO 8601] ISO 8601:1988 - Data elements and interchange formats -
Information interchange - Representation of dates and
times - The International Organization for
Standardization, June, 1988.
[ISO 8601 TC] ISO 8601, Technical Corrigendum 1 - Data elements and
interchange formats - Information interchange -
Representation of dates and times - The International
Organization for Standardization, May, 1991.
[ISO 9070] ISO 9070, Information Processing - SGML support
facilities - Registration Procedures for Public Text
Owner Identifiers, April, 1991.
[CCITT E.163] Recommendation E.163 - Numbering Plan for The
International Telephone Service, CCITT Blue Book,
Fascicle II.2, pp. 128-134, November, 1988.
[CCITT X.121] Recommendation X.121 - International Numbering Plan for
Public Data Networks, CCITT Blue Book, Fascicle VIII.3,
pp. 317-332, November, 1988.
[CCITT X.520] Recommendation X.520 - The Directory - Selected
Attribute Types, November 1988.
[CCITT X.521] Recommendation X.521 - The Directory - Selected Object
Classes, November 1988.
[MIME-DIR] Howes, T., Smith, M., and F. Dawson, "A MIME Content-
Type for Directory Information", RFC 2425, September
1998.
[RFC 1738] Berners-Lee, T., Masinter, L., and M. McCahill,
"Uniform Resource Locators (URL)", RFC 1738, December
1994.
[RFC 1766] Alvestrand, H., "Tags for the Identification of
Languages", RFC 1766, March 1995.
Dawson & Howes Standards Track [Page 40]
RFC 2426 vCard MIME Directory Profile September 1998
[RFC 1872] Levinson, E., "The MIME Multipart/Related Content-
type", RFC 1872, December 1995.
[RFC 2045] Freed, N., and N. Borenstein, "Multipurpose Internet
Mail Extensions (MIME) - Part One: Format of Internet
Message Bodies", RFC 2045, November 1996.
[RFC 2046] Freed, N., and N. Borenstein, "Multipurpose Internet
Mail Extensions (MIME) - Part Two: Media Types", RFC
2046, November 1996.
[RFC 2047] Moore, K., "Multipurpose Internet Mail Extensions
(MIME) - Part Three: Message Header Extensions for
Non-ASCII Text", RFC 2047, November 1996.
[RFC 2048] Freed, N., Klensin, J., and J. Postel, "Multipurpose
Internet Mail Extensions (MIME) - Part Four:
Registration Procedures", RFC 2048, January 1997.
[RFC 2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC 2234] Crocker, D., and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
[UNICODE] "The Unicode Standard - Version 2.0", The Unicode
Consortium, July 1996.
[VCARD] Internet Mail Consortium, "vCard - The Electronic
Business Card Version 2.1",
http://www.imc.org/pdi/vcard-21.txt, September 18,
1996.
Dawson & Howes Standards Track [Page 41]
RFC 2426 vCard MIME Directory Profile September 1998
10. Full Copyright Statement
Copyright (C) The Internet Society (1998). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Dawson & Howes Standards Track [Page 42]
Network Working Group F. Dawson
Request for Comments: 2445 Lotus
Category: Standards Track D. Stenerson
Microsoft
November 1998
Internet Calendaring and Scheduling Core Object Specification
(iCalendar)
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (1998). All Rights Reserved.
Abstract
There is a clear need to provide and deploy interoperable calendaring
and scheduling services for the Internet. Current group scheduling
and Personal Information Management (PIM) products are being extended
for use across the Internet, today, in proprietary ways. This memo
has been defined to provide the definition of a common format for
openly exchanging calendaring and scheduling information across the
Internet.
This memo is formatted as a registration for a MIME media type per
[RFC 2048]. However, the format in this memo is equally applicable
for use outside of a MIME message content type.
The proposed media type value is 'text/calendar'. This string would
label a media type containing calendaring and scheduling information
encoded as text characters formatted in a manner outlined below.
This MIME media type provides a standard content type for capturing
calendar event, to-do and journal entry information. It also can be
used to convey free/busy time information. The content type is
suitable as a MIME message entity that can be transferred over MIME
based email systems, using HTTP or some other Internet transport. In
Dawson & Stenerson Standards Track [Page 1]
RFC 2445 iCalendar November 1998
addition, the content type is useful as an object for interactions
between desktop applications using the operating system clipboard,
drag/drop or file systems capabilities.
This memo is based on the earlier work of the vCalendar specification
for the exchange of personal calendaring and scheduling information.
In order to avoid confusion with this referenced work, this memo is
to be known as the iCalendar specification.
This memo defines the format for specifying iCalendar object methods.
An iCalendar object method is a set of usage constraints for the
iCalendar object. For example, these methods might define scheduling
messages that request an event be scheduled, reply to an event
request, send a cancellation notice for an event, modify or replace
the definition of an event, provide a counter proposal for an
original event request, delegate an event request to another
individual, request free or busy time, reply to a free or busy time
request, or provide similar scheduling messages for a to-do or
journal entry calendar component. The iCalendar Transport-indendent
Interoperability Protocol (iTIP) defined in [ITIP] is one such
scheduling protocol.
Table of Contents
1 Introduction.....................................................5
2 Basic Grammar and Conventions....................................6
2.1 Formatting Conventions .......................................7
2.2 Related Memos ................................................8
2.3 International Considerations .................................8
3 Registration Information.........................................8
3.1 Content Type .................................................8
3.2 Parameters ...................................................9
3.3 Content Header Fields .......................................10
3.4 Encoding Considerations .....................................10
3.5 Security Considerations .....................................10
3.6 Interoperability Considerations .............................11
3.7 Applications Which Use This Media Type ......................11
3.8 Additional Information ......................................11
3.9 Magic Numbers ...............................................11
3.10 File Extensions ............................................11
3.11 Contact for Further Information: ...........................12
3.12 Intended Usage .............................................12
3.13 Authors/Change Controllers .................................12
4 iCalendar Object Specification..................................13
4.1 Content Lines ...............................................13
4.1.1 List and Field Separators ................................16
4.1.2 Multiple Values ..........................................16
4.1.3 Binary Content ...........................................16
Dawson & Stenerson Standards Track [Page 2]
RFC 2445 iCalendar November 1998
4.1.4 Character Set ............................................17
4.2 Property Parameters .........................................17
4.2.1 Alternate Text Representation ............................18
4.2.2 Common Name ..............................................19
4.2.3 Calendar User Type .......................................20
4.2.4 Delegators ...............................................20
4.2.5 Delegatees ...............................................21
4.2.6 Directory Entry Reference ................................21
4.2.7 Inline Encoding ..........................................22
4.2.8 Format Type ..............................................23
4.2.9 Free/Busy Time Type ......................................23
4.2.10 Language ................................................24
4.2.11 Group or List Membership ................................25
4.2.12 Participation Status ....................................25
4.2.13 Recurrence Identifier Range .............................27
4.2.14 Alarm Trigger Relationship ..............................27
4.2.15 Relationship Type .......................................28
4.2.16 Participation Role ......................................29
4.2.17 RSVP Expectation ........................................29
4.2.18 Sent By .................................................30
4.2.19 Time Zone Identifier ....................................30
4.2.20 Value Data Types ........................................32
4.3 Property Value Data Types ...................................32
4.3.1 Binary ...................................................33
4.3.2 Boolean ..................................................33
4.3.3 Calendar User Address ....................................34
4.3.4 Date .....................................................34
4.3.5 Date-Time ................................................35
4.3.6 Duration .................................................37
4.3.7 Float ....................................................38
4.3.8 Integer ..................................................38
4.3.9 Period of Time ...........................................39
4.3.10 Recurrence Rule .........................................40
4.3.11 Text ....................................................45
4.3.12 Time ....................................................47
4.3.13 URI .....................................................49
4.3.14 UTC Offset ..............................................49
4.4 iCalendar Object ............................................50
4.5 Property ....................................................51
4.6 Calendar Components .........................................51
4.6.1 Event Component ..........................................52
4.6.2 To-do Component ..........................................55
4.6.3 Journal Component ........................................56
4.6.4 Free/Busy Component ......................................58
4.6.5 Time Zone Component ......................................60
4.6.6 Alarm Component ..........................................67
4.7 Calendar Properties .........................................73
4.7.1 Calendar Scale ...........................................73
Dawson & Stenerson Standards Track [Page 3]
RFC 2445 iCalendar November 1998
4.7.2 Method ...................................................74
4.7.3 Product Identifier .......................................75
4.7.4 Version ..................................................76
4.8 Component Properties ........................................77
4.8.1 Descriptive Component Properties .........................77
4.8.1.1 Attachment ...........................................77
4.8.1.2 Categories ...........................................78
4.8.1.3 Classification .......................................79
4.8.1.4 Comment ..............................................80
4.8.1.5 Description ..........................................81
4.8.1.6 Geographic Position ..................................82
4.8.1.7 Location .............................................84
4.8.1.8 Percent Complete .....................................85
4.8.1.9 Priority .............................................85
4.8.1.10 Resources ...........................................87
4.8.1.11 Status ..............................................88
4.8.1.12 Summary .............................................89
4.8.2 Date and Time Component Properties .......................90
4.8.2.1 Date/Time Completed ..................................90
4.8.2.2 Date/Time End ........................................91
4.8.2.3 Date/Time Due ........................................92
4.8.2.4 Date/Time Start ......................................93
4.8.2.5 Duration .............................................94
4.8.2.6 Free/Busy Time .......................................95
4.8.2.7 Time Transparency ....................................96
4.8.3 Time Zone Component Properties ...........................97
4.8.3.1 Time Zone Identifier .................................97
4.8.3.2 Time Zone Name .......................................98
4.8.3.3 Time Zone Offset From ................................99
4.8.3.4 Time Zone Offset To .................................100
4.8.3.5 Time Zone URL .......................................101
4.8.4 Relationship Component Properties .......................102
4.8.4.1 Attendee ............................................102
4.8.4.2 Contact .............................................104
4.8.4.3 Organizer ...........................................106
4.8.4.4 Recurrence ID .......................................107
4.8.4.5 Related To ..........................................109
4.8.4.6 Uniform Resource Locator ............................110
4.8.4.7 Unique Identifier ...................................111
4.8.5 Recurrence Component Properties .........................112
4.8.5.1 Exception Date/Times ................................112
4.8.5.2 Exception Rule ......................................114
4.8.5.3 Recurrence Date/Times ...............................115
4.8.5.4 Recurrence Rule .....................................117
4.8.6 Alarm Component Properties ..............................126
4.8.6.1 Action ..............................................126
4.8.6.2 Repeat Count ........................................126
4.8.6.3 Trigger .............................................127
Dawson & Stenerson Standards Track [Page 4]
RFC 2445 iCalendar November 1998
4.8.7 Change Management Component Properties ..................129
4.8.7.1 Date/Time Created ...................................129
4.8.7.2 Date/Time Stamp .....................................130
4.8.7.3 Last Modified .......................................131
4.8.7.4 Sequence Number .....................................131
4.8.8 Miscellaneous Component Properties ......................133
4.8.8.1 Non-standard Properties .............................133
4.8.8.2 Request Status ......................................134
5 iCalendar Object Examples......................................136
6 Recommended Practices..........................................140
7 Registration of Content Type Elements..........................141
7.1 Registration of New and Modified iCalendar Object Methods ..141
7.2 Registration of New Properties .............................141
7.2.1 Define the property .....................................142
7.2.2 Post the Property definition ............................143
7.2.3 Allow a comment period ..................................143
7.2.4 Submit the property for approval ........................143
7.3 Property Change Control ....................................143
8 References.....................................................144
9 Acknowledgments................................................145
10 Authors' and Chairs' Addresses................................146
11 Full Copyright Statement......................................148
1 Introduction
The use of calendaring and scheduling has grown considerably in the
last decade. Enterprise and inter-enterprise business has become
dependent on rapid scheduling of events and actions using this
information technology. However, the longer term growth of
calendaring and scheduling, is currently limited by the lack of
Internet standards for the message content types that are central to
these knowledgeware applications. This memo is intended to progress
the level of interoperability possible between dissimilar calendaring
and scheduling applications. This memo defines a MIME content type
for exchanging electronic calendaring and scheduling information. The
Internet Calendaring and Scheduling Core Object Specification, or
iCalendar, allows for the capture and exchange of information
normally stored within a calendaring and scheduling application; such
as a Personal Information Manager (PIM) or a Group Scheduling
product.
The iCalendar format is suitable as an exchange format between
applications or systems. The format is defined in terms of a MIME
content type. This will enable the object to be exchanged using
several transports, including but not limited to SMTP, HTTP, a file
system, desktop interactive protocols such as the use of a memory-
based clipboard or drag/drop interactions, point-to-point
asynchronous communication, wired-network transport, or some form of
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unwired transport such as infrared might also be used.
The memo also provides for the definition of iCalendar object methods
that will map this content type to a set of messages for supporting
calendaring and scheduling operations such as requesting, replying
to, modifying, and canceling meetings or appointments, to-dos and
journal entries. The iCalendar object methods can be used to define
other calendaring and scheduling operations such a requesting for and
replying with free/busy time data. Such a scheduling protocol is
defined in the iCalendar Transport-independent Interoperability
Protocol (iTIP) defined in [ITIP].
The memo also includes a formal grammar for the content type based on
the Internet ABNF defined in [RFC 2234]. This ABNF is required for
the implementation of parsers and to serve as the definitive
reference when ambiguities or questions arise in interpreting the
descriptive prose definition of the memo.
2 Basic Grammar and Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY" and
"OPTIONAL" in this document are to be interoperated as described in
[RFC 2119].
This memo makes use of both a descriptive prose and a more formal
notation for defining the calendaring and scheduling format.
The notation used in this memo is the ABNF notation of [RFC 2234].
Readers intending on implementing this format defined in this memo
should be familiar with this notation in order to properly interpret
the specifications of this memo.
All numeric and hexadecimal values used in this memo are given in
decimal notation.
All names of properties, property parameters, enumerated property
values and property parameter values are case-insensitive. However,
all other property values are case-sensitive, unless otherwise
stated.
Note: All indented editorial notes, such as this one, are
intended to provide the reader with additional information. The
information is not essential to the building of an
implementation conformant with this memo. The information is
provided to highlight a particular feature or characteristic of
the memo.
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The format for the iCalendar object is based on the syntax of the
[RFC 2425] content type. While the iCalendar object is not a profile
of the [RFC 2425] content type, it does reuse a number of the
elements from the [RFC 2425] specification.
2.1 Formatting Conventions
The mechanisms defined in this memo are defined in prose. Many of the
terms used to describe these have common usage that is different than
the standards usage of this memo. In order to reference within this
memo elements of the calendaring and scheduling model, core object
(this memo) or interoperability protocol [ITIP] some formatting
conventions have been used. Calendaring and scheduling roles are
referred to in quoted-strings of text with the first character of
each word in upper case. For example, "Organizer" refers to a role of
a "Calendar User" within the scheduling protocol defined by [ITIP].
Calendar components defined by this memo are referred to with
capitalized, quoted-strings of text. All calendar components start
with the letter "V". For example, "VEVENT" refers to the event
calendar component, "VTODO" refers to the to-do calendar component
and "VJOURNAL" refers to the daily journal calendar component.
Scheduling methods defined by [ITIP] are referred to with
capitalized, quoted-strings of text. For example, "REQUEST" refers to
the method for requesting a scheduling calendar component be created
or modified, "REPLY" refers to the method a recipient of a request
uses to update their status with the "Organizer" of the calendar
component.
The properties defined by this memo are referred to with capitalized,
quoted-strings of text, followed by the word "property". For example,
"ATTENDEE" property refers to the iCalendar property used to convey
the calendar address of a calendar user. Property parameters defined
by this memo are referred to with lowercase, quoted-strings of text,
followed by the word "parameter". For example, "value" parameter
refers to the iCalendar property parameter used to override the
default data type for a property value. Enumerated values defined by
this memo are referred to with capitalized text, either alone or
followed by the word "value". For example, the "MINUTELY" value can
be used with the "FREQ" component of the "RECUR" data type to specify
repeating components based on an interval of one minute or more.
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2.2 Related Memos
Implementers will need to be familiar with several other memos that,
along with this memo, form a framework for Internet calendaring and
scheduling standards. This memo, [ICAL], specifies a core
specification of objects, data types, properties and property
parameters.
[ITIP] - specifies an interoperability protocol for scheduling
between different implementations;
[IMIP] specifies an Internet email binding for [ITIP].
This memo does not attempt to repeat the specification of concepts or
definitions from these other memos. Where possible, references are
made to the memo that provides for the specification of these
concepts or definitions.
2.3 International Considerations
In the rest of this document, descriptions of characters are of the
form "character name (codepoint)", where "codepoint" is from the US-
ASCII character set. The "character name" is the authoritative
description; (codepoint) is a reference to that character in US-ASCII
or US-ASCII compatible sets (for example the ISO-8859-x family, UTF-
8, ISO-2022-xx, KOI8-R). If a non-US-ASCII compatible character set
is used, appropriate code-point from that character set MUST be
chosen instead. Use of non-US-ASCII-compatible character sets is NOT
recommended.
3 Registration Information
The Calendaring and Scheduling Core Object Specification is intended
for use as a MIME content type. However, the implementation of the
memo is in no way limited solely as a MIME content type.
3.1 Content Type
The following text is intended to register this memo as the MIME
content type "text/calendar".
To: ietf-types@uninett.no
Subject: Registration of MIME content type text/calendar.
MIME media type name: text
MIME subtype name: calendar
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3.2 Parameters
Required parameters: none
Optional parameters: charset, method, component and optinfo
The "charset" parameter is defined in [RFC 2046] for other body
parts. It is used to identify the default character set used within
the body part.
The "method" parameter is used to convey the iCalendar object method
or transaction semantics for the calendaring and scheduling
information. It also is an identifier for the restricted set of
properties and values that the iCalendar object consists of. The
parameter is to be used as a guide for applications interpreting the
information contained within the body part. It SHOULD NOT be used to
exclude or require particular pieces of information unless the
identified method definition specifically calls for this behavior.
Unless specifically forbidden by a particular method definition, a
text/calendar content type can contain any set of properties
permitted by the Calendaring and Scheduling Core Object
Specification. The "method" parameter MUST be the same value as that
specified in the "METHOD" component property in the iCalendar object.
If one is present, the other MUST also be present.
The value for the "method" parameter is defined as follows:
method = 1*(ALPHA / DIGIT / "-")
; IANA registered iCalendar object method
The "component" parameter conveys the type of iCalendar calendar
component within the body part. If the iCalendar object contains more
than one calendar component type, then multiple component parameters
MUST be specified.
The value for the "component" parameter is defined as follows:
component = ("VEVENT" / "VTODO" / "VJOURNAL" / "VFREEBUSY"
/ "VTIMEZONE" / x-name / iana-token)
The "optinfo" parameter conveys optional information about the
iCalendar object within the body part. This parameter can only
specify semantics already specified by the iCalendar object and that
can be otherwise determined by parsing the body part. In addition,
the optional information specified by this parameter MUST be
consistent with that information specified by the iCalendar object.
For example, it can be used to convey the "Attendee" response status
to a meeting request. The parameter value consists of a string value.
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The parameter can be specified multiple times.
This parameter MAY only specify semantics already specified by the
iCalendar object and that can be otherwise determined by parsing the
body part.
The value for the "optinfo" parameter is defined as follows:
optinfo = infovalue / qinfovalue
infovalue = iana-token / x-name
qinfovalue = DQUOTE (infovalue) DQUOTE
3.3 Content Header Fields
Optional content header fields: Any header fields defined by [RFC
2045].
3.4 Encoding Considerations
This MIME content type can contain 8bit characters, so the use of
quoted-printable or BASE64 MIME content-transfer-encodings might be
necessary when iCalendar objects are transferred across protocols
restricted to the 7bit repertoire. Note that a text valued property
in the content entity can also have content encoding of special
characters using a BACKSLASH character (US-ASCII decimal 92)
escapement technique. This means that content values can end up
encoded twice.
3.5 Security Considerations
SPOOFING - - In this memo, the "Organizer" is the only person
authorized to make changes to an existing "VEVENT", "VTODO",
"VJOURNAL" calendar component and redistribute the updates to the
"Attendees". An iCalendar object that maliciously changes or cancels
an existing "VEVENT", "VTODO" or "VJOURNAL" or "VFREEBUSY" calendar
component might be constructed by someone other than the "Organizer"
and sent to the "Attendees". In addition in this memo, other than the
"Organizer", an "Attendee" of a "VEVENT", "VTODO", "VJOURNAL"
calendar component is the only other person authorized to update any
parameter associated with their "ATTENDEE" property and send it to
the "Organizer". An iCalendar object that maliciously changes the
"ATTENDEE" parameters can be constructed by someone other than the
real "Attendee" and sent to the "Organizer".
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RFC 2445 iCalendar November 1998
PROCEDURAL ALARMS - - An iCalendar object can be created that
contains a "VEVENT" and "VTODO" calendar component with "VALARM"
calendar components. The "VALARM" calendar component can be of type
PROCEDURE and can have an attachment containing some sort of
executable program. Implementations that incorporate these types of
alarms are subject to any virus or malicious attack that might occur
as a result of executing the attachment.
ATTACHMENTS - - An iCalendar object can include references to Uniform
Resource Locators that can be programmed resources.
Implementers and users of this memo should be aware of the network
security implications of accepting and parsing such information. In
addition, the security considerations observed by implementations of
electronic mail systems should be followed for this memo.
3.6 Interoperability Considerations
This MIME content type is intended to define a common format for
conveying calendaring and scheduling information between different
systems. It is heavily based on the earlier [VCAL] industry
specification.
3.7 Applications Which Use This Media Type
This content-type is designed for widespread use by Internet
calendaring and scheduling applications. In addition, applications in
the workflow and document management area might find this content-
type applicable. The [ITIP] and [IMIP] Internet protocols directly
use this content-type also. Future work on an Internet calendar
access protocol will utilize this content-type too.
3.8 Additional Information
This memo defines this content-type.
3.9 Magic Numbers
None.
3.10 File Extensions
The file extension of "ics" is to be used to designate a file
containing (an arbitrary set of) calendaring and scheduling
information consistent with this MIME content type.
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The file extension of "ifb" is to be used to designate a file
containing free or busy time information consistent with this MIME
content type.
Macintosh file type codes: The file type code of "iCal" is to be used
in Apple MacIntosh operating system environments to designate a file
containing calendaring and scheduling information consistent with
this MIME media type.
The file type code of "iFBf" is to be used in Apple MacIntosh
operating system environments to designate a file containing free or
busy time information consistent with this MIME media type.
3.11 Contact for Further Information:
Frank Dawson
6544 Battleford Drive
Raleigh, NC 27613-3502
919-676-9515 (Telephone)
919-676-9564 (Data/Facsimile)
Frank_Dawson@Lotus.com (Internet Mail)
Derik Stenerson
One Microsoft Way
Redmond, WA 98052-6399
425-936-5522 (Telephone)
425-936-7329 (Facsimile)
deriks@microsoft.com (Internet Mail)
3.12 Intended Usage
COMMON
3.13 Authors/Change Controllers
Frank Dawson
6544 Battleford Drive
Raleigh, NC 27613-3502
919-676-9515 (Telephone)
919-676-9564 (Data/Facsimile)
Frank_Dawson@Lotus.com (Internet Mail)
Derik Stenerson
One Microsoft Way
Redmond, WA 98052-6399
425-936-5522 (Telephone)
425-936-7329 (Facsimile)
deriks@microsoft.com (Internet Mail)
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4 iCalendar Object Specification
The following sections define the details of a Calendaring and
Scheduling Core Object Specification. This information is intended to
be an integral part of the MIME content type registration. In
addition, this information can be used independent of such content
registration. In particular, this memo has direct applicability for
use as a calendaring and scheduling exchange format in file-, memory-
or network-based transport mechanisms.
4.1 Content Lines
The iCalendar object is organized into individual lines of text,
called content lines. Content lines are delimited by a line break,
which is a CRLF sequence (US-ASCII decimal 13, followed by US-ASCII
decimal 10).
Lines of text SHOULD NOT be longer than 75 octets, excluding the line
break. Long content lines SHOULD be split into a multiple line
representations using a line "folding" technique. That is, a long
line can be split between any two characters by inserting a CRLF
immediately followed by a single linear white space character (i.e.,
SPACE, US-ASCII decimal 32 or HTAB, US-ASCII decimal 9). Any sequence
of CRLF followed immediately by a single linear white space character
is ignored (i.e., removed) when processing the content type.
For example the line:
DESCRIPTION:This is a long description that exists on a long line.
Can be represented as:
DESCRIPTION:This is a lo
ng description
that exists on a long line.
The process of moving from this folded multiple line representation
to its single line representation is called "unfolding". Unfolding is
accomplished by removing the CRLF character and the linear white
space character that immediately follows.
When parsing a content line, folded lines MUST first be unfolded
according to the unfolding procedure described above. When generating
a content line, lines longer than 75 octets SHOULD be folded
according to the folding procedure described above.
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The content information associated with an iCalendar object is
formatted using a syntax similar to that defined by [RFC 2425]. That
is, the content information consists of CRLF-separated content lines.
The following notation defines the lines of content in an iCalendar
object:
contentline = name *(";" param ) ":" value CRLF
; This ABNF is just a general definition for an initial parsing
; of the content line into its property name, parameter list,
; and value string
; When parsing a content line, folded lines MUST first
; be unfolded according to the unfolding procedure
; described above. When generating a content line, lines
; longer than 75 octets SHOULD be folded according to
; the folding procedure described above.
name = x-name / iana-token
iana-token = 1*(ALPHA / DIGIT / "-")
; iCalendar identifier registered with IANA
x-name = "X-" [vendorid "-"] 1*(ALPHA / DIGIT / "-")
; Reservered for experimental use. Not intended for use in
; released products.
vendorid = 3*(ALPHA / DIGIT) ;Vendor identification
param = param-name "=" param-value
*("," param-value)
; Each property defines the specific ABNF for the parameters
; allowed on the property. Refer to specific properties for
; precise parameter ABNF.
param-name = iana-token / x-token
param-value = paramtext / quoted-string
paramtext = *SAFE-CHAR
value = *VALUE-CHAR
quoted-string = DQUOTE *QSAFE-CHAR DQUOTE
NON-US-ASCII = %x80-F8
; Use restricted by charset parameter
; on outer MIME object (UTF-8 preferred)
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RFC 2445 iCalendar November 1998
QSAFE-CHAR = WSP / %x21 / %x23-7E / NON-US-ASCII
; Any character except CTLs and DQUOTE
SAFE-CHAR = WSP / %x21 / %x23-2B / %x2D-39 / %x3C-7E
/ NON-US-ASCII
; Any character except CTLs, DQUOTE, ";", ":", ","
VALUE-CHAR = WSP / %x21-7E / NON-US-ASCII
; Any textual character
CR = %x0D
; carriage return
LF = %x0A
; line feed
CRLF = CR LF
; Internet standard newline
CTL = %x00-08 / %x0A-1F / %x7F
; Controls
ALPHA = %x41-5A / %x61-7A ; A-Z / a-z
DIGIT = %x30-39
; 0-9
DQUOTE = %x22
; Quotation Mark
WSP = SPACE / HTAB
SPACE = %x20
HTAB = %x09
The property value component of a content line has a format that is
property specific. Refer to the section describing each property for
a definition of this format.
All names of properties, property parameters, enumerated property
values and property parameter values are case-insensitive. However,
all other property values are case-sensitive, unless otherwise
stated.
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4.1.1 List and Field Separators
Some properties and parameters allow a list of values. Values in a
list of values MUST be separated by a COMMA character (US-ASCII
decimal 44). There is no significance to the order of values in a
list. For those parameter values (such as those that specify URI
values) that are specified in quoted-strings, the individual quoted-
strings are separated by a COMMA character (US-ASCII decimal 44).
Some property values are defined in terms of multiple parts. These
structured property values MUST have their value parts separated by a
SEMICOLON character (US-ASCII decimal 59).
Some properties allow a list of parameters. Each property parameter
in a list of property parameters MUST be separated by a SEMICOLON
character (US-ASCII decimal 59).
Property parameters with values containing a COLON, a SEMICOLON or a
COMMA character MUST be placed in quoted text.
For example, in the following properties a SEMICOLON is used to
separate property parameters from each other, and a COMMA is used to
separate property values in a value list.
ATTENDEE;RSVP=TRUE;ROLE=REQ-PARTICIPANT:MAILTO:
jsmith@host.com
RDATE;VALUE=DATE:19970304,19970504,19970704,19970904
4.1.2 Multiple Values
Some properties defined in the iCalendar object can have multiple
values. The general rule for encoding multi-valued items is to simply
create a new content line for each value, including the property
name. However, it should be noted that some properties support
encoding multiple values in a single property by separating the
values with a COMMA character (US-ASCII decimal 44). Individual
property definitions should be consulted for determining whether a
specific property allows multiple values and in which of these two
forms.
4.1.3 Binary Content
Binary content information in an iCalendar object SHOULD be
referenced using a URI within a property value. That is the binary
content information SHOULD be placed in an external MIME entity that
can be referenced by a URI from within the iCalendar object. In
applications where this is not feasible, binary content information
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can be included within an iCalendar object, but only after first
encoding it into text using the "BASE64" encoding method defined in
[RFC 2045]. Inline binary contact SHOULD only be used in applications
whose special circumstances demand that an iCalendar object be
expressed as a single entity. A property containing inline binary
content information MUST specify the "ENCODING" property parameter.
Binary content information placed external to the iCalendar object
MUST be referenced by a uniform resource identifier (URI).
The following example specifies an "ATTACH" property that references
an attachment external to the iCalendar object with a URI reference:
ATTACH:http://xyz.com/public/quarterly-report.doc
The following example specifies an "ATTACH" property with inline
binary encoded content information:
ATTACH;FMTTYPE=image/basic;ENCODING=BASE64;VALUE=BINARY:
MIICajCCAdOgAwIBAgICBEUwDQYJKoZIhvcNAQEEBQAwdzELMAkGA1U
EBhMCVVMxLDAqBgNVBAoTI05ldHNjYXBlIENvbW11bmljYXRpb25zIE
<...remainder of "BASE64" encoded binary data...>
4.1.4 Character Set
There is not a property parameter to declare the character set used
in a property value. The default character set for an iCalendar
object is UTF-8 as defined in [RFC 2279].
The "charset" Content-Type parameter can be used in MIME transports
to specify any other IANA registered character set.
4.2 Property Parameters
A property can have attributes associated with it. These "property
parameters" contain meta-information about the property or the
property value. Property parameters are provided to specify such
information as the location of an alternate text representation for a
property value, the language of a text property value, the data type
of the property value and other attributes.
Property parameter values that contain the COLON (US-ASCII decimal
58), SEMICOLON (US-ASCII decimal 59) or COMMA (US-ASCII decimal 44)
character separators MUST be specified as quoted-string text values.
Property parameter values MUST NOT contain the DOUBLE-QUOTE (US-ASCII
decimal 22) character. The DOUBLE-QUOTE (US-ASCII decimal 22)
character is used as a delimiter for parameter values that contain
restricted characters or URI text. For example:
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RFC 2445 iCalendar November 1998
DESCRIPTION;ALTREP="http://www.wiz.org":The Fall'98 Wild Wizards
Conference - - Las Vegas, NV, USA
Property parameter values that are not in quoted strings are case
insensitive.
The general property parameters defined by this memo are defined by
the following notation:
parameter = altrepparam ; Alternate text representation
/ cnparam ; Common name
/ cutypeparam ; Calendar user type
/ delfromparam ; Delegator
/ deltoparam ; Delegatee
/ dirparam ; Directory entry
/ encodingparam ; Inline encoding
/ fmttypeparam ; Format type
/ fbtypeparam ; Free/busy time type
/ languageparam ; Language for text
/ memberparam ; Group or list membership
/ partstatparam ; Participation status
/ rangeparam ; Recurrence identifier range
/ trigrelparam ; Alarm trigger relationship
/ reltypeparam ; Relationship type
/ roleparam ; Participation role
/ rsvpparam ; RSVP expectation
/ sentbyparam ; Sent by
/ tzidparam ; Reference to time zone object
/ valuetypeparam ; Property value data type
/ ianaparam
; Some other IANA registered iCalendar parameter.
/ xparam
; A non-standard, experimental parameter.
ianaparam = iana-token "=" param-value *("," param-value)
xparam =x-name "=" param-value *("," param-value)
4.2.1 Alternate Text Representation
Parameter Name: ALTREP
Purpose: To specify an alternate text representation for the property
value.
Format Definition: The property parameter is defined by the following
notation:
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RFC 2445 iCalendar November 1998
altrepparam = "ALTREP" "=" DQUOTE uri DQUOTE
Description: The parameter specifies a URI that points to an
alternate representation for a textual property value. A property
specifying this parameter MUST also include a value that reflects the
default representation of the text value. The individual URI
parameter values MUST each be specified in a quoted-string.
Example:
DESCRIPTION;ALTREP="CID:<part3.msg.970415T083000@host.com>":Project
XYZ Review Meeting will include the following agenda items: (a)
Market Overview, (b) Finances, (c) Project Management
The "ALTREP" property parameter value might point to a "text/html"
content portion.
Content-Type:text/html
Content-Id:<part3.msg.970415T083000@host.com>
<html><body>
<p><b>Project XYZ Review Meeting</b> will include the following
agenda items:<ol><li>Market
Overview</li><li>Finances</li><li>Project Management</li></ol></p>
</body></html>
4.2.2 Common Name
Parameter Name: CN
Purpose: To specify the common name to be associated with the
calendar user specified by the property.
Format Definition: The property parameter is defined by the following
notation:
cnparam = "CN" "=" param-value
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. The parameter specifies the common name to be
associated with the calendar user specified by the property. The
parameter value is text. The parameter value can be used for display
text to be associated with the calendar address specified by the
property.
Dawson & Stenerson Standards Track [Page 19]
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Example:
ORGANIZER;CN="John Smith":MAILTO:jsmith@host.com
4.2.3 Calendar User Type
Parameter Name: CUTYPE
Purpose: To specify the type of calendar user specified by the
property.
Format Definition: The property parameter is defined by the following
notation:
cutypeparam = "CUTYPE" "="
("INDIVIDUAL" ; An individual
/ "GROUP" ; A group of individuals
/ "RESOURCE" ; A physical resource
/ "ROOM" ; A room resource
/ "UNKNOWN" ; Otherwise not known
/ x-name ; Experimental type
/ iana-token) ; Other IANA registered
; type
; Default is INDIVIDUAL
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. The parameter identifies the type of calendar
user specified by the property. If not specified on a property that
allows this parameter, the default is INDIVIDUAL.
Example:
ATTENDEE;CUTYPE=GROUP:MAILTO:ietf-calsch@imc.org
4.2.4 Delegators
Parameter Name: DELEGATED-FROM
Purpose: To specify the calendar users that have delegated their
participation to the calendar user specified by the property.
Format Definition: The property parameter is defined by the following
notation:
delfromparam = "DELEGATED-FROM" "=" DQUOTE cal-address DQUOTE
*("," DQUOTE cal-address DQUOTE)
Dawson & Stenerson Standards Track [Page 20]
RFC 2445 iCalendar November 1998
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. This parameter can be specified on a property
that has a value type of calendar address. This parameter specifies
those calendar uses that have delegated their participation in a
group scheduled event or to-do to the calendar user specified by the
property. The value MUST be a MAILTO URI as defined in [RFC 1738].
The individual calendar address parameter values MUST each be
specified in a quoted-string.
Example:
ATTENDEE;DELEGATED-FROM="MAILTO:jsmith@host.com":MAILTO:
jdoe@host.com
4.2.5 Delegatees
Parameter Name: DELEGATED-TO
Purpose: To specify the calendar users to whom the calendar user
specified by the property has delegated participation.
Format Definition: The property parameter is defined by the following
notation:
deltoparam = "DELEGATED-TO" "=" DQUOTE cal-address DQUOTE
*("," DQUOTE cal-address DQUOTE)
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. This parameter specifies those calendar users
whom have been delegated participation in a group scheduled event or
to-do by the calendar user specified by the property. The value MUST
be a MAILTO URI as defined in [RFC 1738]. The individual calendar
address parameter values MUST each be specified in a quoted-string.
Example:
ATTENDEE;DELEGATED-TO="MAILTO:jdoe@host.com","MAILTO:jqpublic@
host.com":MAILTO:jsmith@host.com
4.2.6 Directory Entry Reference
Parameter Name: DIR
Purpose: To specify reference to a directory entry associated with
the calendar user specified by the property.
Format Definition: The property parameter is defined by the following
notation:
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dirparam = "DIR" "=" DQUOTE uri DQUOTE
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. The parameter specifies a reference to the
directory entry associated with the calendar user specified by the
property. The parameter value is a URI. The individual URI parameter
values MUST each be specified in a quoted-string.
Example:
ORGANIZER;DIR="ldap://host.com:6666/o=eDABC%20Industries,c=3DUS??
(cn=3DBJim%20Dolittle)":MAILTO:jimdo@host1.com
4.2.7 Inline Encoding
Parameter Name: ENCODING
Purpose: To specify an alternate inline encoding for the property
value.
Format Definition: The property parameter is defined by the following
notation:
encodingparam = "ENCODING" "="
("8BIT"
; "8bit" text encoding is defined in [RFC 2045]
/ "BASE64"
; "BASE64" binary encoding format is defined in [RFC 2045]
/ iana-token
; Some other IANA registered iCalendar encoding type
/ x-name)
; A non-standard, experimental encoding type
Description: The property parameter identifies the inline encoding
used in a property value. The default encoding is "8BIT",
corresponding to a property value consisting of text. The "BASE64"
encoding type corresponds to a property value encoded using the
"BASE64" encoding defined in [RFC 2045].
If the value type parameter is ";VALUE=BINARY", then the inline
encoding parameter MUST be specified with the value
";ENCODING=BASE64".
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Example:
ATTACH;FMTYPE=IMAGE/JPEG;ENCODING=BASE64;VALUE=BINARY:MIICajC
CAdOgAwIBAgICBEUwDQYJKoZIhvcNAQEEBQAwdzELMAkGA1UEBhMCVVMxLDA
qBgNVBAoTI05ldHNjYXBlIENvbW11bmljYXRpb25zIENvcnBvcmF0aW9uMRw
<...remainder of "BASE64" encoded binary data...>
4.2.8 Format Type
Parameter Name: FMTTYPE
Purpose: To specify the content type of a referenced object.
Format Definition: The property parameter is defined by the following
notation:
fmttypeparam = "FMTTYPE" "=" iana-token
; A IANA registered content type
/ x-name
; A non-standard content type
Description: This parameter can be specified on properties that are
used to reference an object. The parameter specifies the content type
of the referenced object. For example, on the "ATTACH" property, a
FTP type URI value does not, by itself, necessarily convey the type
of content associated with the resource. The parameter value MUST be
the TEXT for either an IANA registered content type or a non-standard
content type.
Example:
ATTACH;FMTTYPE=application/binary:ftp://domain.com/pub/docs/
agenda.doc
4.2.9 Free/Busy Time Type
Parameter Name: FBTYPE
Purpose: To specify the free or busy time type.
Format Definition: The property parameter is defined by the following
notation:
fbtypeparam = "FBTYPE" "=" ("FREE" / "BUSY"
/ "BUSY-UNAVAILABLE" / "BUSY-TENTATIVE"
/ x-name
; Some experimental iCalendar data type.
/ iana-token)
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; Some other IANA registered iCalendar data type.
Description: The parameter specifies the free or busy time type. The
value FREE indicates that the time interval is free for scheduling.
The value BUSY indicates that the time interval is busy because one
or more events have been scheduled for that interval. The value
BUSY-UNAVAILABLE indicates that the time interval is busy and that
the interval can not be scheduled. The value BUSY-TENTATIVE indicates
that the time interval is busy because one or more events have been
tentatively scheduled for that interval. If not specified on a
property that allows this parameter, the default is BUSY.
Example: The following is an example of this parameter on a FREEBUSY
property.
FREEBUSY;FBTYPE=BUSY:19980415T133000Z/19980415T170000Z
4.2.10 Language
Parameter Name: LANGUAGE
Purpose: To specify the language for text values in a property or
property parameter.
Format Definition: The property parameter is defined by the following
notation:
languageparam = "LANGUAGE" "=" language
language = <Text identifying a language, as defined in [RFC 1766]>
Description: This parameter can be specified on properties with a
text value type. The parameter identifies the language of the text in
the property or property parameter value. The value of the "language"
property parameter is that defined in [RFC 1766].
For transport in a MIME entity, the Content-Language header field can
be used to set the default language for the entire body part.
Otherwise, no default language is assumed.
Example:
SUMMARY;LANGUAGE=us-EN:Company Holiday Party
LOCATION;LANGUAGE=en:Germany
LOCATION;LANGUAGE=no:Tyskland
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The following example makes use of the Quoted-Printable encoding in
order to represent non-ASCII characters.
LOCATION;LANGUAGE=da:K=F8benhavn
LOCATION;LANGUAGE=en:Copenhagen
4.2.11 Group or List Membership
Parameter Name: MEMBER
Purpose: To specify the group or list membership of the calendar user
specified by the property.
Format Definition: The property parameter is defined by the following
notation:
memberparam = "MEMBER" "=" DQUOTE cal-address DQUOTE
*("," DQUOTE cal-address DQUOTE)
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. The parameter identifies the groups or list
membership for the calendar user specified by the property. The
parameter value either a single calendar address in a quoted-string
or a COMMA character (US-ASCII decimal 44) list of calendar
addresses, each in a quoted-string. The individual calendar address
parameter values MUST each be specified in a quoted-string.
Example:
ATTENDEE;MEMBER="MAILTO:ietf-calsch@imc.org":MAILTO:jsmith@host.com
ATTENDEE;MEMBER="MAILTO:projectA@host.com","MAILTO:projectB@host.
com":MAILTO:janedoe@host.com
4.2.12 Participation Status
Parameter Name: PARTSTAT
Purpose: To specify the participation status for the calendar user
specified by the property.
Format Definition: The property parameter is defined by the following
notation:
partstatparam = "PARTSTAT" "="
("NEEDS-ACTION" ; Event needs action
/ "ACCEPTED" ; Event accepted
/ "DECLINED" ; Event declined
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/ "TENTATIVE" ; Event tentatively
; accepted
/ "DELEGATED" ; Event delegated
/ x-name ; Experimental status
/ iana-token) ; Other IANA registered
; status
; These are the participation statuses for a "VEVENT". Default is
; NEEDS-ACTION
partstatparam /= "PARTSTAT" "="
("NEEDS-ACTION" ; To-do needs action
/ "ACCEPTED" ; To-do accepted
/ "DECLINED" ; To-do declined
/ "TENTATIVE" ; To-do tentatively
; accepted
/ "DELEGATED" ; To-do delegated
/ "COMPLETED" ; To-do completed.
; COMPLETED property has
;date/time completed.
/ "IN-PROCESS" ; To-do in process of
; being completed
/ x-name ; Experimental status
/ iana-token) ; Other IANA registered
; status
; These are the participation statuses for a "VTODO". Default is
; NEEDS-ACTION
partstatparam /= "PARTSTAT" "="
("NEEDS-ACTION" ; Journal needs action
/ "ACCEPTED" ; Journal accepted
/ "DECLINED" ; Journal declined
/ x-name ; Experimental status
/ iana-token) ; Other IANA registered
; status
; These are the participation statuses for a "VJOURNAL". Default is
; NEEDS-ACTION
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. The parameter identifies the participation
status for the calendar user specified by the property value. The
parameter values differ depending on whether they are associated with
a group scheduled "VEVENT", "VTODO" or "VJOURNAL". The values MUST
match one of the values allowed for the given calendar component. If
not specified on a property that allows this parameter, the default
value is NEEDS-ACTION.
Example:
ATTENDEE;PARTSTAT=DECLINED:MAILTO:jsmith@host.com
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4.2.13 Recurrence Identifier Range
Parameter Name: RANGE
Purpose: To specify the effective range of recurrence instances from
the instance specified by the recurrence identifier specified by the
property.
Format Definition: The property parameter is defined by the following
notation:
rangeparam = "RANGE" "=" ("THISANDPRIOR"
; To specify all instances prior to the recurrence identifier
/ "THISANDFUTURE")
; To specify the instance specified by the recurrence identifier
; and all subsequent recurrence instances
Description: The parameter can be specified on a property that
specifies a recurrence identifier. The parameter specifies the
effective range of recurrence instances that is specified by the
property. The effective range is from the recurrence identified
specified by the property. If this parameter is not specified an
allowed property, then the default range is the single instance
specified by the recurrence identifier value of the property. The
parameter value can be "THISANDPRIOR" to indicate a range defined by
the recurrence identified value of the property and all prior
instances. The parameter value can also be "THISANDFUTURE" to
indicate a range defined by the recurrence identifier and all
subsequent instances.
Example:
RECURRENCE-ID;RANGE=THISANDPRIOR:19980401T133000Z
4.2.14 Alarm Trigger Relationship
Parameter Name: RELATED
Purpose: To specify the relationship of the alarm trigger with
respect to the start or end of the calendar component.
Format Definition: The property parameter is defined by the following
notation:
trigrelparam = "RELATED" "="
("START" ; Trigger off of start
/ "END") ; Trigger off of end
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Description: The parameter can be specified on properties that
specify an alarm trigger with a DURATION value type. The parameter
specifies whether the alarm will trigger relative to the start or end
of the calendar component. The parameter value START will set the
alarm to trigger off the start of the calendar component; the
parameter value END will set the alarm to trigger off the end of the
calendar component. If the parameter is not specified on an allowable
property, then the default is START.
Example:
TRIGGER;RELATED=END:PT5M
4.2.15 Relationship Type
Parameter Name: RELTYPE
Purpose: To specify the type of hierarchical relationship associated
with the calendar component specified by the property.
Format Definition: The property parameter is defined by the following
notation:
reltypeparam = "RELTYPE" "="
("PARENT" ; Parent relationship. Default.
/ "CHILD" ; Child relationship
/ "SIBLING ; Sibling relationship
/ iana-token ; Some other IANA registered
; iCalendar relationship type
/ x-name) ; A non-standard, experimental
; relationship type
Description: This parameter can be specified on a property that
references another related calendar. The parameter specifies the
hierarchical relationship type of the calendar component referenced
by the property. The parameter value can be PARENT, to indicate that
the referenced calendar component is a superior of calendar
component; CHILD to indicate that the referenced calendar component
is a subordinate of the calendar component; SIBLING to indicate that
the referenced calendar component is a peer of the calendar
component. If this parameter is not specified on an allowable
property, the default relationship type is PARENT.
Example:
RELATED-TO;RELTYPE=SIBLING:<19960401-080045-4000F192713@host.com>
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4.2.16 Participation Role
Parameter Name: ROLE
Purpose: To specify the participation role for the calendar user
specified by the property.
Format Definition: The property parameter is defined by the following
notation:
roleparam = "ROLE" "="
("CHAIR" ; Indicates chair of the
; calendar entity
/ "REQ-PARTICIPANT" ; Indicates a participant whose
; participation is required
/ "OPT-PARTICIPANT" ; Indicates a participant whose
; participation is optional
/ "NON-PARTICIPANT" ; Indicates a participant who is
; copied for information
; purposes only
/ x-name ; Experimental role
/ iana-token) ; Other IANA role
; Default is REQ-PARTICIPANT
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. The parameter specifies the participation
role for the calendar user specified by the property in the group
schedule calendar component. If not specified on a property that
allows this parameter, the default value is REQ-PARTICIPANT.
Example:
ATTENDEE;ROLE=CHAIR:MAILTO:mrbig@host.com
4.2.17 RSVP Expectation
Parameter Name: RSVP
Purpose: To specify whether there is an expectation of a favor of a
reply from the calendar user specified by the property value.
Format Definition: The property parameter is defined by the following
notation:
rsvpparam = "RSVP" "=" ("TRUE" / "FALSE")
; Default is FALSE
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Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. The parameter identifies the expectation of a
reply from the calendar user specified by the property value. This
parameter is used by the "Organizer" to request a participation
status reply from an "Attendee" of a group scheduled event or to-do.
If not specified on a property that allows this parameter, the
default value is FALSE.
Example:
ATTENDEE;RSVP=TRUE:MAILTO:jsmith@host.com
4.2.18 Sent By
Parameter Name: SENT-BY
Purpose: To specify the calendar user that is acting on behalf of the
calendar user specified by the property.
Format Definition: The property parameter is defined by the following
notation:
sentbyparam = "SENT-BY" "=" DQUOTE cal-address DQUOTE
Description: This parameter can be specified on properties with a
CAL-ADDRESS value type. The parameter specifies the calendar user
that is acting on behalf of the calendar user specified by the
property. The parameter value MUST be a MAILTO URI as defined in [RFC
1738]. The individual calendar address parameter values MUST each be
specified in a quoted-string.
Example:
ORGANIZER;SENT-BY:"MAILTO:sray@host.com":MAILTO:jsmith@host.com
4.2.19 Time Zone Identifier
Parameter Name: TZID
Purpose: To specify the identifier for the time zone definition for a
time component in the property value.
Format Definition: This property parameter is defined by the
following notation:
tzidparam = "TZID" "=" [tzidprefix] paramtext CRLF
tzidprefix = "/"
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Description: The parameter MUST be specified on the "DTSTART",
"DTEND", "DUE", "EXDATE" and "RDATE" properties when either a DATE-
TIME or TIME value type is specified and when the value is not either
a UTC or a "floating" time. Refer to the DATE-TIME or TIME value type
definition for a description of UTC and "floating time" formats. This
property parameter specifies a text value which uniquely identifies
the "VTIMEZONE" calendar component to be used when evaluating the
time portion of the property. The value of the TZID property
parameter will be equal to the value of the TZID property for the
matching time zone definition. An individual "VTIMEZONE" calendar
component MUST be specified for each unique "TZID" parameter value
specified in the iCalendar object.
The parameter MUST be specified on properties with a DATE-TIME value
if the DATE-TIME is not either a UTC or a "floating" time.
The presence of the SOLIDUS character (US-ASCII decimal 47) as a
prefix, indicates that this TZID represents a unique ID in a globally
defined time zone registry (when such registry is defined).
Note: This document does not define a naming convention for time
zone identifiers. Implementers may want to use the naming
conventions defined in existing time zone specifications such as
the public-domain Olson database [TZ]. The specification of
globally unique time zone identifiers is not addressed by this
document and is left for future study.
The following are examples of this property parameter:
DTSTART;TZID=US-Eastern:19980119T020000
DTEND;TZID=US-Eastern:19980119T030000
The TZID property parameter MUST NOT be applied to DATE-TIME or TIME
properties whose time values are specified in UTC.
The use of local time in a DATE-TIME or TIME value without the TZID
property parameter is to be interpreted as a local time value,
regardless of the existence of "VTIMEZONE" calendar components in the
iCalendar object.
For more information see the sections on the data types DATE-TIME and
TIME.
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4.2.20 Value Data Types
Parameter Name: VALUE
Purpose: To explicitly specify the data type format for a property
value.
Format Definition: The "VALUE" property parameter is defined by the
following notation:
valuetypeparam = "VALUE" "=" valuetype
valuetype = ("BINARY"
/ "BOOLEAN"
/ "CAL-ADDRESS"
/ "DATE"
/ "DATE-TIME"
/ "DURATION"
/ "FLOAT"
/ "INTEGER"
/ "PERIOD"
/ "RECUR"
/ "TEXT"
/ "TIME"
/ "URI"
/ "UTC-OFFSET"
/ x-name
; Some experimental iCalendar data type.
/ iana-token)
; Some other IANA registered iCalendar data type.
Description: The parameter specifies the data type and format of the
property value. The property values MUST be of a single value type.
For example, a "RDATE" property cannot have a combination of DATE-
TIME and TIME value types.
If the property's value is the default value type, then this
parameter need not be specified. However, if the property's default
value type is overridden by some other allowable value type, then
this parameter MUST be specified.
4.3 Property Value Data Types
The properties in an iCalendar object are strongly typed. The
definition of each property restricts the value to be one of the
value data types, or simply value types, defined in this section. The
value type for a property will either be specified implicitly as the
default value type or will be explicitly specified with the "VALUE"
Dawson & Stenerson Standards Track [Page 32]
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parameter. If the value type of a property is one of the alternate
valid types, then it MUST be explicitly specified with the "VALUE"
parameter.
4.3.1 Binary
Value Name: BINARY
Purpose: This value type is used to identify properties that contain
a character encoding of inline binary data. For example, an inline
attachment of an object code might be included in an iCalendar
object.
Formal Definition: The value type is defined by the following
notation:
binary = *(4b-char) [b-end]
; A "BASE64" encoded character string, as defined by [RFC 2045].
b-end = (2b-char "==") / (3b-char "=")
b-char = ALPHA / DIGIT / "+" / "/"
Description: Property values with this value type MUST also include
the inline encoding parameter sequence of ";ENCODING=BASE64". That
is, all inline binary data MUST first be character encoded using the
"BASE64" encoding method defined in [RFC 2045]. No additional content
value encoding (i.e., BACKSLASH character encoding) is defined for
this value type.
Example: The following is an abridged example of a "BASE64" encoded
binary value data.
ATTACH;VALUE=BINARY;ENCODING=BASE64:MIICajCCAdOgAwIBAgICBEUwDQY
JKoZIhvcNAQEEBQAwdzELMAkGA1UEBhMCVVMxLDAqBgNVBAoTI05ldHNjYXBlI
ENvbW11bmljYXRpb25zIENvcnBvcmF0aW9uMRwwGgYDVQQLExNJbmZv
<...remainder of "BASE64" encoded binary data...>
4.3.2 Boolean
Value Name: BOOLEAN
Purpose: This value type is used to identify properties that contain
either a "TRUE" or "FALSE" Boolean value.
Formal Definition: The value type is defined by the following
notation:
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boolean = "TRUE" / "FALSE"
Description: These values are case insensitive text. No additional
content value encoding (i.e., BACKSLASH character encoding) is
defined for this value type.
Example: The following is an example of a hypothetical property that
has a BOOLEAN value type:
GIBBERISH:TRUE
4.3.3 Calendar User Address
Value Name: CAL-ADDRESS
Purpose: This value type is used to identify properties that contain
a calendar user address.
Formal Definition: The value type is as defined by the following
notation:
cal-address = uri
Description: The value is a URI as defined by [RFC 1738] or any other
IANA registered form for a URI. When used to address an Internet
email transport address for a calendar user, the value MUST be a
MAILTO URI, as defined by [RFC 1738]. No additional content value
encoding (i.e., BACKSLASH character encoding) is defined for this
value type.
Example:
ATTENDEE:MAILTO:jane_doe@host.com
4.3.4 Date
Value Name: DATE
Purpose: This value type is used to identify values that contain a
calendar date.
Formal Definition: The value type is defined by the following
notation:
date = date-value
date-value = date-fullyear date-month date-mday
date-fullyear = 4DIGIT
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date-month = 2DIGIT ;01-12
date-mday = 2DIGIT ;01-28, 01-29, 01-30, 01-31
;based on month/year
Description: If the property permits, multiple "date" values are
specified as a COMMA character (US-ASCII decimal 44) separated list
of values. The format for the value type is expressed as the [ISO
8601] complete representation, basic format for a calendar date. The
textual format specifies a four-digit year, two-digit month, and
two-digit day of the month. There are no separator characters between
the year, month and day component text.
No additional content value encoding (i.e., BACKSLASH character
encoding) is defined for this value type.
Example: The following represents July 14, 1997:
19970714
4.3.5 Date-Time
Value Name: DATE-TIME
Purpose: This value type is used to identify values that specify a
precise calendar date and time of day.
Formal Definition: The value type is defined by the following
notation:
date-time = date "T" time ;As specified in the date and time
;value definitions
Description: If the property permits, multiple "date-time" values are
specified as a COMMA character (US-ASCII decimal 44) separated list
of values. No additional content value encoding (i.e., BACKSLASH
character encoding) is defined for this value type.
The "DATE-TIME" data type is used to identify values that contain a
precise calendar date and time of day. The format is based on the
[ISO 8601] complete representation, basic format for a calendar date
and time of day. The text format is a concatenation of the "date",
followed by the LATIN CAPITAL LETTER T character (US-ASCII decimal
84) time designator, followed by the "time" format.
The "DATE-TIME" data type expresses time values in three forms:
The form of date and time with UTC offset MUST NOT be used. For
example, the following is not valid for a date-time value:
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DTSTART:19980119T230000-0800 ;Invalid time format
FORM #1: DATE WITH LOCAL TIME
The date with local time form is simply a date-time value that does
not contain the UTC designator nor does it reference a time zone. For
example, the following represents Janurary 18, 1998, at 11 PM:
DTSTART:19980118T230000
Date-time values of this type are said to be "floating" and are not
bound to any time zone in particular. They are used to represent the
same hour, minute, and second value regardless of which time zone is
currently being observed. For example, an event can be defined that
indicates that an individual will be busy from 11:00 AM to 1:00 PM
every day, no matter which time zone the person is in. In these
cases, a local time can be specified. The recipient of an iCalendar
object with a property value consisting of a local time, without any
relative time zone information, SHOULD interpret the value as being
fixed to whatever time zone the ATTENDEE is in at any given moment.
This means that two ATTENDEEs, in different time zones, receiving the
same event definition as a floating time, may be participating in the
event at different actual times. Floating time SHOULD only be used
where that is the reasonable behavior.
In most cases, a fixed time is desired. To properly communicate a
fixed time in a property value, either UTC time or local time with
time zone reference MUST be specified.
The use of local time in a DATE-TIME value without the TZID property
parameter is to be interpreted as floating time, regardless of the
existence of "VTIMEZONE" calendar components in the iCalendar object.
FORM #2: DATE WITH UTC TIME
The date with UTC time, or absolute time, is identified by a LATIN
CAPITAL LETTER Z suffix character (US-ASCII decimal 90), the UTC
designator, appended to the time value. For example, the following
represents January 19, 1998, at 0700 UTC:
DTSTART:19980119T070000Z
The TZID property parameter MUST NOT be applied to DATE-TIME
properties whose time values are specified in UTC.
FORM #3: DATE WITH LOCAL TIME AND TIME ZONE REFERENCE
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The date and local time with reference to time zone information is
identified by the use the TZID property parameter to reference the
appropriate time zone definition. TZID is discussed in detail in the
section on Time Zone. For example, the following represents 2 AM in
New York on Janurary 19, 1998:
DTSTART;TZID=US-Eastern:19980119T020000
Example: The following represents July 14, 1997, at 1:30 PM in New
York City in each of the three time formats, using the "DTSTART"
property.
DTSTART:19970714T133000 ;Local time
DTSTART:19970714T173000Z ;UTC time
DTSTART;TZID=US-Eastern:19970714T133000 ;Local time and time
; zone reference
A time value MUST ONLY specify 60 seconds when specifying the
periodic "leap second" in the time value. For example:
COMPLETED:19970630T235960Z
4.3.6 Duration
Value Name: DURATION
Purpose: This value type is used to identify properties that contain
a duration of time.
Formal Definition: The value type is defined by the following
notation:
dur-value = (["+"] / "-") "P" (dur-date / dur-time / dur-week)
dur-date = dur-day [dur-time]
dur-time = "T" (dur-hour / dur-minute / dur-second)
dur-week = 1*DIGIT "W"
dur-hour = 1*DIGIT "H" [dur-minute]
dur-minute = 1*DIGIT "M" [dur-second]
dur-second = 1*DIGIT "S"
dur-day = 1*DIGIT "D"
Description: If the property permits, multiple "duration" values are
specified by a COMMA character (US-ASCII decimal 44) separated list
of values. The format is expressed as the [ISO 8601] basic format for
the duration of time. The format can represent durations in terms of
weeks, days, hours, minutes, and seconds.
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No additional content value encoding (i.e., BACKSLASH character
encoding) are defined for this value type.
Example: A duration of 15 days, 5 hours and 20 seconds would be:
P15DT5H0M20S
A duration of 7 weeks would be:
P7W
4.3.7 Float
Value Name: FLOAT
Purpose: This value type is used to identify properties that contain
a real number value.
Formal Definition: The value type is defined by the following
notation:
float = (["+"] / "-") 1*DIGIT ["." 1*DIGIT]
Description: If the property permits, multiple "float" values are
specified by a COMMA character (US-ASCII decimal 44) separated list
of values.
No additional content value encoding (i.e., BACKSLASH character
encoding) is defined for this value type.
Example:
1000000.0000001
1.333
-3.14
4.3.8 Integer
Value Name:INTEGER
Purpose: This value type is used to identify properties that contain
a signed integer value.
Formal Definition: The value type is defined by the following
notation:
integer = (["+"] / "-") 1*DIGIT
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Description: If the property permits, multiple "integer" values are
specified by a COMMA character (US-ASCII decimal 44) separated list
of values. The valid range for "integer" is -2147483648 to
2147483647. If the sign is not specified, then the value is assumed
to be positive.
No additional content value encoding (i.e., BACKSLASH character
encoding) is defined for this value type.
Example:
1234567890
-1234567890
+1234567890
432109876
4.3.9 Period of Time
Value Name: PERIOD
Purpose: This value type is used to identify values that contain a
precise period of time.
Formal Definition: The data type is defined by the following
notation:
period = period-explicit / period-start
period-explicit = date-time "/" date-time
; [ISO 8601] complete representation basic format for a period of
; time consisting of a start and end. The start MUST be before the
; end.
period-start = date-time "/" dur-value
; [ISO 8601] complete representation basic format for a period of
; time consisting of a start and positive duration of time.
Description: If the property permits, multiple "period" values are
specified by a COMMA character (US-ASCII decimal 44) separated list
of values. There are two forms of a period of time. First, a period
of time is identified by its start and its end. This format is
expressed as the [ISO 8601] complete representation, basic format for
"DATE-TIME" start of the period, followed by a SOLIDUS character
(US-ASCII decimal 47), followed by the "DATE-TIME" of the end of the
period. The start of the period MUST be before the end of the period.
Second, a period of time can also be defined by a start and a
positive duration of time. The format is expressed as the [ISO 8601]
complete representation, basic format for the "DATE-TIME" start of
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the period, followed by a SOLIDUS character (US-ASCII decimal 47),
followed by the [ISO 8601] basic format for "DURATION" of the period.
Example: The period starting at 18:00:00 UTC, on January 1, 1997 and
ending at 07:00:00 UTC on January 2, 1997 would be:
19970101T180000Z/19970102T070000Z
The period start at 18:00:00 on January 1, 1997 and lasting 5 hours
and 30 minutes would be:
19970101T180000Z/PT5H30M
No additional content value encoding (i.e., BACKSLASH character
encoding) is defined for this value type.
4.3.10 Recurrence Rule
Value Name: RECUR
Purpose: This value type is used to identify properties that contain
a recurrence rule specification.
Formal Definition: The value type is defined by the following
notation:
recur = "FREQ"=freq *(
; either UNTIL or COUNT may appear in a 'recur',
; but UNTIL and COUNT MUST NOT occur in the same 'recur'
( ";" "UNTIL" "=" enddate ) /
( ";" "COUNT" "=" 1*DIGIT ) /
; the rest of these keywords are optional,
; but MUST NOT occur more than once
( ";" "INTERVAL" "=" 1*DIGIT ) /
( ";" "BYSECOND" "=" byseclist ) /
( ";" "BYMINUTE" "=" byminlist ) /
( ";" "BYHOUR" "=" byhrlist ) /
( ";" "BYDAY" "=" bywdaylist ) /
( ";" "BYMONTHDAY" "=" bymodaylist ) /
( ";" "BYYEARDAY" "=" byyrdaylist ) /
( ";" "BYWEEKNO" "=" bywknolist ) /
( ";" "BYMONTH" "=" bymolist ) /
( ";" "BYSETPOS" "=" bysplist ) /
( ";" "WKST" "=" weekday ) /
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( ";" x-name "=" text )
)
freq = "SECONDLY" / "MINUTELY" / "HOURLY" / "DAILY"
/ "WEEKLY" / "MONTHLY" / "YEARLY"
enddate = date
enddate =/ date-time ;An UTC value
byseclist = seconds / ( seconds *("," seconds) )
seconds = 1DIGIT / 2DIGIT ;0 to 59
byminlist = minutes / ( minutes *("," minutes) )
minutes = 1DIGIT / 2DIGIT ;0 to 59
byhrlist = hour / ( hour *("," hour) )
hour = 1DIGIT / 2DIGIT ;0 to 23
bywdaylist = weekdaynum / ( weekdaynum *("," weekdaynum) )
weekdaynum = [([plus] ordwk / minus ordwk)] weekday
plus = "+"
minus = "-"
ordwk = 1DIGIT / 2DIGIT ;1 to 53
weekday = "SU" / "MO" / "TU" / "WE" / "TH" / "FR" / "SA"
;Corresponding to SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY,
;FRIDAY, SATURDAY and SUNDAY days of the week.
bymodaylist = monthdaynum / ( monthdaynum *("," monthdaynum) )
monthdaynum = ([plus] ordmoday) / (minus ordmoday)
ordmoday = 1DIGIT / 2DIGIT ;1 to 31
byyrdaylist = yeardaynum / ( yeardaynum *("," yeardaynum) )
yeardaynum = ([plus] ordyrday) / (minus ordyrday)
ordyrday = 1DIGIT / 2DIGIT / 3DIGIT ;1 to 366
bywknolist = weeknum / ( weeknum *("," weeknum) )
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weeknum = ([plus] ordwk) / (minus ordwk)
bymolist = monthnum / ( monthnum *("," monthnum) )
monthnum = 1DIGIT / 2DIGIT ;1 to 12
bysplist = setposday / ( setposday *("," setposday) )
setposday = yeardaynum
Description: If the property permits, multiple "recur" values are
specified by a COMMA character (US-ASCII decimal 44) separated list
of values. The value type is a structured value consisting of a list
of one or more recurrence grammar parts. Each rule part is defined by
a NAME=VALUE pair. The rule parts are separated from each other by
the SEMICOLON character (US-ASCII decimal 59). The rule parts are not
ordered in any particular sequence. Individual rule parts MUST only
be specified once.
The FREQ rule part identifies the type of recurrence rule. This rule
part MUST be specified in the recurrence rule. Valid values include
SECONDLY, to specify repeating events based on an interval of a
second or more; MINUTELY, to specify repeating events based on an
interval of a minute or more; HOURLY, to specify repeating events
based on an interval of an hour or more; DAILY, to specify repeating
events based on an interval of a day or more; WEEKLY, to specify
repeating events based on an interval of a week or more; MONTHLY, to
specify repeating events based on an interval of a month or more; and
YEARLY, to specify repeating events based on an interval of a year or
more.
The INTERVAL rule part contains a positive integer representing how
often the recurrence rule repeats. The default value is "1", meaning
every second for a SECONDLY rule, or every minute for a MINUTELY
rule, every hour for an HOURLY rule, every day for a DAILY rule,
every week for a WEEKLY rule, every month for a MONTHLY rule and
every year for a YEARLY rule.
The UNTIL rule part defines a date-time value which bounds the
recurrence rule in an inclusive manner. If the value specified by
UNTIL is synchronized with the specified recurrence, this date or
date-time becomes the last instance of the recurrence. If specified
as a date-time value, then it MUST be specified in an UTC time
format. If not present, and the COUNT rule part is also not present,
the RRULE is considered to repeat forever.
The COUNT rule part defines the number of occurrences at which to
range-bound the recurrence. The "DTSTART" property value, if
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specified, counts as the first occurrence.
The BYSECOND rule part specifies a COMMA character (US-ASCII decimal
44) separated list of seconds within a minute. Valid values are 0 to
59. The BYMINUTE rule part specifies a COMMA character (US-ASCII
decimal 44) separated list of minutes within an hour. Valid values
are 0 to 59. The BYHOUR rule part specifies a COMMA character (US-
ASCII decimal 44) separated list of hours of the day. Valid values
are 0 to 23.
The BYDAY rule part specifies a COMMA character (US-ASCII decimal 44)
separated list of days of the week; MO indicates Monday; TU indicates
Tuesday; WE indicates Wednesday; TH indicates Thursday; FR indicates
Friday; SA indicates Saturday; SU indicates Sunday.
Each BYDAY value can also be preceded by a positive (+n) or negative
(-n) integer. If present, this indicates the nth occurrence of the
specific day within the MONTHLY or YEARLY RRULE. For example, within
a MONTHLY rule, +1MO (or simply 1MO) represents the first Monday
within the month, whereas -1MO represents the last Monday of the
month. If an integer modifier is not present, it means all days of
this type within the specified frequency. For example, within a
MONTHLY rule, MO represents all Mondays within the month.
The BYMONTHDAY rule part specifies a COMMA character (ASCII decimal
44) separated list of days of the month. Valid values are 1 to 31 or
-31 to -1. For example, -10 represents the tenth to the last day of
the month.
The BYYEARDAY rule part specifies a COMMA character (US-ASCII decimal
44) separated list of days of the year. Valid values are 1 to 366 or
-366 to -1. For example, -1 represents the last day of the year
(December 31st) and -306 represents the 306th to the last day of the
year (March 1st).
The BYWEEKNO rule part specifies a COMMA character (US-ASCII decimal
44) separated list of ordinals specifying weeks of the year. Valid
values are 1 to 53 or -53 to -1. This corresponds to weeks according
to week numbering as defined in [ISO 8601]. A week is defined as a
seven day period, starting on the day of the week defined to be the
week start (see WKST). Week number one of the calendar year is the
first week which contains at least four (4) days in that calendar
year. This rule part is only valid for YEARLY rules. For example, 3
represents the third week of the year.
Note: Assuming a Monday week start, week 53 can only occur when
Thursday is January 1 or if it is a leap year and Wednesday is
January 1.
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The BYMONTH rule part specifies a COMMA character (US-ASCII decimal
44) separated list of months of the year. Valid values are 1 to 12.
The WKST rule part specifies the day on which the workweek starts.
Valid values are MO, TU, WE, TH, FR, SA and SU. This is significant
when a WEEKLY RRULE has an interval greater than 1, and a BYDAY rule
part is specified. This is also significant when in a YEARLY RRULE
when a BYWEEKNO rule part is specified. The default value is MO.
The BYSETPOS rule part specifies a COMMA character (US-ASCII decimal
44) separated list of values which corresponds to the nth occurrence
within the set of events specified by the rule. Valid values are 1 to
366 or -366 to -1. It MUST only be used in conjunction with another
BYxxx rule part. For example "the last work day of the month" could
be represented as:
RRULE:FREQ=MONTHLY;BYDAY=MO,TU,WE,TH,FR;BYSETPOS=-1
Each BYSETPOS value can include a positive (+n) or negative (-n)
integer. If present, this indicates the nth occurrence of the
specific occurrence within the set of events specified by the rule.
If BYxxx rule part values are found which are beyond the available
scope (ie, BYMONTHDAY=30 in February), they are simply ignored.
Information, not contained in the rule, necessary to determine the
various recurrence instance start time and dates are derived from the
Start Time (DTSTART) entry attribute. For example,
"FREQ=YEARLY;BYMONTH=1" doesn't specify a specific day within the
month or a time. This information would be the same as what is
specified for DTSTART.
BYxxx rule parts modify the recurrence in some manner. BYxxx rule
parts for a period of time which is the same or greater than the
frequency generally reduce or limit the number of occurrences of the
recurrence generated. For example, "FREQ=DAILY;BYMONTH=1" reduces the
number of recurrence instances from all days (if BYMONTH tag is not
present) to all days in January. BYxxx rule parts for a period of
time less than the frequency generally increase or expand the number
of occurrences of the recurrence. For example,
"FREQ=YEARLY;BYMONTH=1,2" increases the number of days within the
yearly recurrence set from 1 (if BYMONTH tag is not present) to 2.
If multiple BYxxx rule parts are specified, then after evaluating the
specified FREQ and INTERVAL rule parts, the BYxxx rule parts are
applied to the current set of evaluated occurrences in the following
order: BYMONTH, BYWEEKNO, BYYEARDAY, BYMONTHDAY, BYDAY, BYHOUR,
BYMINUTE, BYSECOND and BYSETPOS; then COUNT and UNTIL are evaluated.
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Here is an example of evaluating multiple BYxxx rule parts.
DTSTART;TZID=US-Eastern:19970105T083000
RRULE:FREQ=YEARLY;INTERVAL=2;BYMONTH=1;BYDAY=SU;BYHOUR=8,9;
BYMINUTE=30
First, the "INTERVAL=2" would be applied to "FREQ=YEARLY" to arrive
at "every other year". Then, "BYMONTH=1" would be applied to arrive
at "every January, every other year". Then, "BYDAY=SU" would be
applied to arrive at "every Sunday in January, every other year".
Then, "BYHOUR=8,9" would be applied to arrive at "every Sunday in
January at 8 AM and 9 AM, every other year". Then, "BYMINUTE=30"
would be applied to arrive at "every Sunday in January at 8:30 AM and
9:30 AM, every other year". Then, lacking information from RRULE, the
second is derived from DTSTART, to end up in "every Sunday in January
at 8:30:00 AM and 9:30:00 AM, every other year". Similarly, if the
BYMINUTE, BYHOUR, BYDAY, BYMONTHDAY or BYMONTH rule part were
missing, the appropriate minute, hour, day or month would have been
retrieved from the "DTSTART" property.
No additional content value encoding (i.e., BACKSLASH character
encoding) is defined for this value type.
Example: The following is a rule which specifies 10 meetings which
occur every other day:
FREQ=DAILY;COUNT=10;INTERVAL=2
There are other examples specified in the "RRULE" specification.
4.3.11 Text
Value Name: TEXT
Purpose This value type is used to identify values that contain human
readable text.
Formal Definition: The character sets supported by this revision of
iCalendar are UTF-8 and US ASCII thereof. The applicability to other
character sets is for future work. The value type is defined by the
following notation.
text = *(TSAFE-CHAR / ":" / DQUOTE / ESCAPED-CHAR)
; Folded according to description above
ESCAPED-CHAR = "\\" / "\;" / "\," / "\N" / "\n")
; \\ encodes \, \N or \n encodes newline
; \; encodes ;, \, encodes ,
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TSAFE-CHAR = %x20-21 / %x23-2B / %x2D-39 / %x3C-5B
%x5D-7E / NON-US-ASCII
; Any character except CTLs not needed by the current
; character set, DQUOTE, ";", ":", "\", ","
Note: Certain other character sets may require modification of the
above definitions, but this is beyond the scope of this document.
Description: If the property permits, multiple "text" values are
specified by a COMMA character (US-ASCII decimal 44) separated list
of values.
The language in which the text is represented can be controlled by
the "LANGUAGE" property parameter.
An intentional formatted text line break MUST only be included in a
"TEXT" property value by representing the line break with the
character sequence of BACKSLASH (US-ASCII decimal 92), followed by a
LATIN SMALL LETTER N (US-ASCII decimal 110) or a LATIN CAPITAL LETTER
N (US-ASCII decimal 78), that is "\n" or "\N".
The "TEXT" property values may also contain special characters that
are used to signify delimiters, such as a COMMA character for lists
of values or a SEMICOLON character for structured values. In order to
support the inclusion of these special characters in "TEXT" property
values, they MUST be escaped with a BACKSLASH character. A BACKSLASH
character (US-ASCII decimal 92) in a "TEXT" property value MUST be
escaped with another BACKSLASH character. A COMMA character in a
"TEXT" property value MUST be escaped with a BACKSLASH character
(US-ASCII decimal 92). A SEMICOLON character in a "TEXT" property
value MUST be escaped with a BACKSLASH character (US-ASCII decimal
92). However, a COLON character in a "TEXT" property value SHALL NOT
be escaped with a BACKSLASH character.Example: A multiple line value
of:
Project XYZ Final Review
Conference Room - 3B
Come Prepared.
would be represented as:
Project XYZ Final Review\nConference Room - 3B\nCome Prepared.
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4.3.12 Time
Value Name: TIME
Purpose: This value type is used to identify values that contain a
time of day.
Formal Definition: The data type is defined by the following
notation:
time = time-hour time-minute time-second [time-utc]
time-hour = 2DIGIT ;00-23
time-minute = 2DIGIT ;00-59
time-second = 2DIGIT ;00-60
;The "60" value is used to account for "leap" seconds.
time-utc = "Z"
Description: If the property permits, multiple "time" values are
specified by a COMMA character (US-ASCII decimal 44) separated list
of values. No additional content value encoding (i.e., BACKSLASH
character encoding) is defined for this value type.
The "TIME" data type is used to identify values that contain a time
of day. The format is based on the [ISO 8601] complete
representation, basic format for a time of day. The text format
consists of a two-digit 24-hour of the day (i.e., values 0-23), two-
digit minute in the hour (i.e., values 0-59), and two-digit seconds
in the minute (i.e., values 0-60). The seconds value of 60 MUST only
to be used to account for "leap" seconds. Fractions of a second are
not supported by this format.
In parallel to the "DATE-TIME" definition above, the "TIME" data type
expresses time values in three forms:
The form of time with UTC offset MUST NOT be used. For example, the
following is NOT VALID for a time value:
230000-0800 ;Invalid time format
FORM #1 LOCAL TIME
The local time form is simply a time value that does not contain the
UTC designator nor does it reference a time zone. For example, 11:00
PM:
230000
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Time values of this type are said to be "floating" and are not bound
to any time zone in particular. They are used to represent the same
hour, minute, and second value regardless of which time zone is
currently being observed. For example, an event can be defined that
indicates that an individual will be busy from 11:00 AM to 1:00 PM
every day, no matter which time zone the person is in. In these
cases, a local time can be specified. The recipient of an iCalendar
object with a property value consisting of a local time, without any
relative time zone information, SHOULD interpret the value as being
fixed to whatever time zone the ATTENDEE is in at any given moment.
This means that two ATTENDEEs may participate in the same event at
different UTC times; floating time SHOULD only be used where that is
reasonable behavior.
In most cases, a fixed time is desired. To properly communicate a
fixed time in a property value, either UTC time or local time with
time zone reference MUST be specified.
The use of local time in a TIME value without the TZID property
parameter is to be interpreted as a local time value, regardless of
the existence of "VTIMEZONE" calendar components in the iCalendar
object.
FORM #2: UTC TIME
UTC time, or absolute time, is identified by a LATIN CAPITAL LETTER Z
suffix character (US-ASCII decimal 90), the UTC designator, appended
to the time value. For example, the following represents 07:00 AM
UTC:
070000Z
The TZID property parameter MUST NOT be applied to TIME properties
whose time values are specified in UTC.
FORM #3: LOCAL TIME AND TIME ZONE REFERENCE
The local time with reference to time zone information form is
identified by the use the TZID property parameter to reference the
appropriate time zone definition. TZID is discussed in detail in the
section on Time Zone.
Example: The following represents 8:30 AM in New York in Winter, five
hours behind UTC, in each of the three formats using the "X-
TIMEOFDAY" non-standard property:
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RFC 2445 iCalendar November 1998
X-TIMEOFDAY:083000
X-TIMEOFDAY:133000Z
X-TIMEOFDAY;TZID=US-Eastern:083000
4.3.13 URI
Value Name: URI
Purpose: This value type is used to identify values that contain a
uniform resource identifier (URI) type of reference to the property
value.
Formal Definition: The data type is defined by the following
notation:
uri = <As defined by any IETF RFC>
Description: This data type might be used to reference binary
information, for values that are large, or otherwise undesirable to
include directly in the iCalendar object.
The URI value formats in RFC 1738, RFC 2111 and any other IETF
registered value format can be specified.
Any IANA registered URI format can be used. These include, but are
not limited to, those defined in RFC 1738 and RFC 2111.
When a property parameter value is a URI value type, the URI MUST be
specified as a quoted-string value.
No additional content value encoding (i.e., BACKSLASH character
encoding) is defined for this value type.
Example: The following is a URI for a network file:
http://host1.com/my-report.txt
4.3.14 UTC Offset
Value Name: UTC-OFFSET
Purpose: This value type is used to identify properties that contain
an offset from UTC to local time.
Formal Definition: The data type is defined by the following
notation:
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utc-offset = time-numzone ;As defined above in time data type
time-numzone = ("+" / "-") time-hour time-minute [time-
second]
Description: The PLUS SIGN character MUST be specified for positive
UTC offsets (i.e., ahead of UTC). The value of "-0000" and "-000000"
are not allowed. The time-second, if present, may not be 60; if
absent, it defaults to zero.
No additional content value encoding (i.e., BACKSLASH character
encoding) is defined for this value type.
Example: The following UTC offsets are given for standard time for
New York (five hours behind UTC) and Geneva (one hour ahead of UTC):
-0500
+0100
4.4 iCalendar Object
The Calendaring and Scheduling Core Object is a collection of
calendaring and scheduling information. Typically, this information
will consist of a single iCalendar object. However, multiple
iCalendar objects can be sequentially grouped together. The first
line and last line of the iCalendar object MUST contain a pair of
iCalendar object delimiter strings. The syntax for an iCalendar
object is as follows:
icalobject = 1*("BEGIN" ":" "VCALENDAR" CRLF
icalbody
"END" ":" "VCALENDAR" CRLF)
The following is a simple example of an iCalendar object:
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//hacksw/handcal//NONSGML v1.0//EN
BEGIN:VEVENT
DTSTART:19970714T170000Z
DTEND:19970715T035959Z
SUMMARY:Bastille Day Party
END:VEVENT
END:VCALENDAR
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4.5 Property
A property is the definition of an individual attribute describing a
calendar or a calendar component. A property takes the form defined
by the "contentline" notation defined in section 4.1.1.
The following is an example of a property:
DTSTART:19960415T133000Z
This memo imposes no ordering of properties within an iCalendar
object.
Property names, parameter names and enumerated parameter values are
case insensitive. For example, the property name "DUE" is the same as
"due" and "Due", DTSTART;TZID=US-Eastern:19980714T120000 is the same
as DtStart;TzID=US-Eastern:19980714T120000.
4.6 Calendar Components
The body of the iCalendar object consists of a sequence of calendar
properties and one or more calendar components. The calendar
properties are attributes that apply to the calendar as a whole. The
calendar components are collections of properties that express a
particular calendar semantic. For example, the calendar component can
specify an event, a to-do, a journal entry, time zone information, or
free/busy time information, or an alarm.
The body of the iCalendar object is defined by the following
notation:
icalbody = calprops component
calprops = 2*(
; 'prodid' and 'version' are both REQUIRED,
; but MUST NOT occur more than once
prodid /version /
; 'calscale' and 'method' are optional,
; but MUST NOT occur more than once
calscale /
method /
x-prop
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RFC 2445 iCalendar November 1998
)
component = 1*(eventc / todoc / journalc / freebusyc /
/ timezonec / iana-comp / x-comp)
iana-comp = "BEGIN" ":" iana-token CRLF
1*contentline
"END" ":" iana-token CRLF
x-comp = "BEGIN" ":" x-name CRLF
1*contentline
"END" ":" x-name CRLF
An iCalendar object MUST include the "PRODID" and "VERSION" calendar
properties. In addition, it MUST include at least one calendar
component. Special forms of iCalendar objects are possible to publish
just busy time (i.e., only a "VFREEBUSY" calendar component) or time
zone (i.e., only a "VTIMEZONE" calendar component) information. In
addition, a complex iCalendar object is possible that is used to
capture a complete snapshot of the contents of a calendar (e.g.,
composite of many different calendar components). More commonly, an
iCalendar object will consist of just a single "VEVENT", "VTODO" or
"VJOURNAL" calendar component.
4.6.1 Event Component
Component Name: "VEVENT"
Purpose: Provide a grouping of component properties that describe an
event.
Format Definition: A "VEVENT" calendar component is defined by the
following notation:
eventc = "BEGIN" ":" "VEVENT" CRLF
eventprop *alarmc
"END" ":" "VEVENT" CRLF
eventprop = *(
; the following are optional,
; but MUST NOT occur more than once
class / created / description / dtstart / geo /
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last-mod / location / organizer / priority /
dtstamp / seq / status / summary / transp /
uid / url / recurid /
; either 'dtend' or 'duration' may appear in
; a 'eventprop', but 'dtend' and 'duration'
; MUST NOT occur in the same 'eventprop'
dtend / duration /
; the following are optional,
; and MAY occur more than once
attach / attendee / categories / comment /
contact / exdate / exrule / rstatus / related /
resources / rdate / rrule / x-prop
)
Description: A "VEVENT" calendar component is a grouping of component
properties, and possibly including "VALARM" calendar components, that
represents a scheduled amount of time on a calendar. For example, it
can be an activity; such as a one-hour long, department meeting from
8:00 AM to 9:00 AM, tomorrow. Generally, an event will take up time
on an individual calendar. Hence, the event will appear as an opaque
interval in a search for busy time. Alternately, the event can have
its Time Transparency set to "TRANSPARENT" in order to prevent
blocking of the event in searches for busy time.
The "VEVENT" is also the calendar component used to specify an
anniversary or daily reminder within a calendar. These events have a
DATE value type for the "DTSTART" property instead of the default
data type of DATE-TIME. If such a "VEVENT" has a "DTEND" property, it
MUST be specified as a DATE value also. The anniversary type of
"VEVENT" can span more than one date (i.e, "DTEND" property value is
set to a calendar date after the "DTSTART" property value).
The "DTSTART" property for a "VEVENT" specifies the inclusive start
of the event. For recurring events, it also specifies the very first
instance in the recurrence set. The "DTEND" property for a "VEVENT"
calendar component specifies the non-inclusive end of the event. For
cases where a "VEVENT" calendar component specifies a "DTSTART"
property with a DATE data type but no "DTEND" property, the events
non-inclusive end is the end of the calendar date specified by the
"DTSTART" property. For cases where a "VEVENT" calendar component
specifies a "DTSTART" property with a DATE-TIME data type but no
"DTEND" property, the event ends on the same calendar date and time
of day specified by the "DTSTART" property.
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The "VEVENT" calendar component cannot be nested within another
calendar component. However, "VEVENT" calendar components can be
related to each other or to a "VTODO" or to a "VJOURNAL" calendar
component with the "RELATED-TO" property.
Example: The following is an example of the "VEVENT" calendar
component used to represent a meeting that will also be opaque to
searches for busy time:
BEGIN:VEVENT
UID:19970901T130000Z-123401@host.com
DTSTAMP:19970901T1300Z
DTSTART:19970903T163000Z
DTEND:19970903T190000Z
SUMMARY:Annual Employee Review
CLASS:PRIVATE
CATEGORIES:BUSINESS,HUMAN RESOURCES
END:VEVENT
The following is an example of the "VEVENT" calendar component used
to represent a reminder that will not be opaque, but rather
transparent, to searches for busy time:
BEGIN:VEVENT
UID:19970901T130000Z-123402@host.com
DTSTAMP:19970901T1300Z
DTSTART:19970401T163000Z
DTEND:19970402T010000Z
SUMMARY:Laurel is in sensitivity awareness class.
CLASS:PUBLIC
CATEGORIES:BUSINESS,HUMAN RESOURCES
TRANSP:TRANSPARENT
END:VEVENT
The following is an example of the "VEVENT" calendar component used
to represent an anniversary that will occur annually. Since it takes
up no time, it will not appear as opaque in a search for busy time;
no matter what the value of the "TRANSP" property indicates:
BEGIN:VEVENT
UID:19970901T130000Z-123403@host.com
DTSTAMP:19970901T1300Z
DTSTART:19971102
SUMMARY:Our Blissful Anniversary
CLASS:CONFIDENTIAL
CATEGORIES:ANNIVERSARY,PERSONAL,SPECIAL OCCASION
RRULE:FREQ=YEARLY
END:VEVENT
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4.6.2 To-do Component
Component Name: VTODO
Purpose: Provide a grouping of calendar properties that describe a
to-do.
Formal Definition: A "VTODO" calendar component is defined by the
following notation:
todoc = "BEGIN" ":" "VTODO" CRLF
todoprop *alarmc
"END" ":" "VTODO" CRLF
todoprop = *(
; the following are optional,
; but MUST NOT occur more than once
class / completed / created / description / dtstamp /
dtstart / geo / last-mod / location / organizer /
percent / priority / recurid / seq / status /
summary / uid / url /
; either 'due' or 'duration' may appear in
; a 'todoprop', but 'due' and 'duration'
; MUST NOT occur in the same 'todoprop'
due / duration /
; the following are optional,
; and MAY occur more than once
attach / attendee / categories / comment / contact /
exdate / exrule / rstatus / related / resources /
rdate / rrule / x-prop
)
Description: A "VTODO" calendar component is a grouping of component
properties and possibly "VALARM" calendar components that represent
an action-item or assignment. For example, it can be used to
represent an item of work assigned to an individual; such as "turn in
travel expense today".
The "VTODO" calendar component cannot be nested within another
calendar component. However, "VTODO" calendar components can be
related to each other or to a "VTODO" or to a "VJOURNAL" calendar
component with the "RELATED-TO" property.
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A "VTODO" calendar component without the "DTSTART" and "DUE" (or
"DURATION") properties specifies a to-do that will be associated with
each successive calendar date, until it is completed.
Example: The following is an example of a "VTODO" calendar component:
BEGIN:VTODO
UID:19970901T130000Z-123404@host.com
DTSTAMP:19970901T1300Z
DTSTART:19970415T133000Z
DUE:19970416T045959Z
SUMMARY:1996 Income Tax Preparation
CLASS:CONFIDENTIAL
CATEGORIES:FAMILY,FINANCE
PRIORITY:1
STATUS:NEEDS-ACTION
END:VTODO
4.6.3 Journal Component
Component Name: VJOURNAL
Purpose: Provide a grouping of component properties that describe a
journal entry.
Formal Definition: A "VJOURNAL" calendar component is defined by the
following notation:
journalc = "BEGIN" ":" "VJOURNAL" CRLF
jourprop
"END" ":" "VJOURNAL" CRLF
jourprop = *(
; the following are optional,
; but MUST NOT occur more than once
class / created / description / dtstart / dtstamp /
last-mod / organizer / recurid / seq / status /
summary / uid / url /
; the following are optional,
; and MAY occur more than once
attach / attendee / categories / comment /
contact / exdate / exrule / related / rdate /
rrule / rstatus / x-prop
Dawson & Stenerson Standards Track [Page 56]
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)
Description: A "VJOURNAL" calendar component is a grouping of
component properties that represent one or more descriptive text
notes associated with a particular calendar date. The "DTSTART"
property is used to specify the calendar date that the journal entry
is associated with. Generally, it will have a DATE value data type,
but it can also be used to specify a DATE-TIME value data type.
Examples of a journal entry include a daily record of a legislative
body or a journal entry of individual telephone contacts for the day
or an ordered list of accomplishments for the day. The "VJOURNAL"
calendar component can also be used to associate a document with a
calendar date.
The "VJOURNAL" calendar component does not take up time on a
calendar. Hence, it does not play a role in free or busy time
searches - - it is as though it has a time transparency value of
TRANSPARENT. It is transparent to any such searches.
The "VJOURNAL" calendar component cannot be nested within another
calendar component. However, "VJOURNAL" calendar components can be
related to each other or to a "VEVENT" or to a "VTODO" calendar
component, with the "RELATED-TO" property.
Example: The following is an example of the "VJOURNAL" calendar
component:
BEGIN:VJOURNAL
UID:19970901T130000Z-123405@host.com
DTSTAMP:19970901T1300Z
DTSTART;VALUE=DATE:19970317
SUMMARY:Staff meeting minutes
DESCRIPTION:1. Staff meeting: Participants include Joe\, Lisa
and Bob. Aurora project plans were reviewed. There is currently
no budget reserves for this project. Lisa will escalate to
management. Next meeting on Tuesday.\n
2. Telephone Conference: ABC Corp. sales representative called
to discuss new printer. Promised to get us a demo by Friday.\n
3. Henry Miller (Handsoff Insurance): Car was totaled by tree.
Is looking into a loaner car. 654-2323 (tel).
END:VJOURNAL
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4.6.4 Free/Busy Component
Component Name: VFREEBUSY
Purpose: Provide a grouping of component properties that describe
either a request for free/busy time, describe a response to a request
for free/busy time or describe a published set of busy time.
Formal Definition: A "VFREEBUSY" calendar component is defined by the
following notation:
freebusyc = "BEGIN" ":" "VFREEBUSY" CRLF
fbprop
"END" ":" "VFREEBUSY" CRLF
fbprop = *(
; the following are optional,
; but MUST NOT occur more than once
contact / dtstart / dtend / duration / dtstamp /
organizer / uid / url /
; the following are optional,
; and MAY occur more than once
attendee / comment / freebusy / rstatus / x-prop
)
Description: A "VFREEBUSY" calendar component is a grouping of
component properties that represents either a request for, a reply to
a request for free or busy time information or a published set of
busy time information.
When used to request free/busy time information, the "ATTENDEE"
property specifies the calendar users whose free/busy time is being
requested; the "ORGANIZER" property specifies the calendar user who
is requesting the free/busy time; the "DTSTART" and "DTEND"
properties specify the window of time for which the free/busy time is
being requested; the "UID" and "DTSTAMP" properties are specified to
assist in proper sequencing of multiple free/busy time requests.
When used to reply to a request for free/busy time, the "ATTENDEE"
property specifies the calendar user responding to the free/busy time
request; the "ORGANIZER" property specifies the calendar user that
originally requested the free/busy time; the "FREEBUSY" property
specifies the free/busy time information (if it exists); and the
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"UID" and "DTSTAMP" properties are specified to assist in proper
sequencing of multiple free/busy time replies.
When used to publish busy time, the "ORGANIZER" property specifies
the calendar user associated with the published busy time; the
"DTSTART" and "DTEND" properties specify an inclusive time window
that surrounds the busy time information; the "FREEBUSY" property
specifies the published busy time information; and the "DTSTAMP"
property specifies the date/time that iCalendar object was created.
The "VFREEBUSY" calendar component cannot be nested within another
calendar component. Multiple "VFREEBUSY" calendar components can be
specified within an iCalendar object. This permits the grouping of
Free/Busy information into logical collections, such as monthly
groups of busy time information.
The "VFREEBUSY" calendar component is intended for use in iCalendar
object methods involving requests for free time, requests for busy
time, requests for both free and busy, and the associated replies.
Free/Busy information is represented with the "FREEBUSY" property.
This property provides a terse representation of time periods. One or
more "FREEBUSY" properties can be specified in the "VFREEBUSY"
calendar component.
When present in a "VFREEBUSY" calendar component, the "DTSTART" and
"DTEND" properties SHOULD be specified prior to any "FREEBUSY"
properties. In a free time request, these properties can be used in
combination with the "DURATION" property to represent a request for a
duration of free time within a specified window of time.
The recurrence properties ("RRULE", "EXRULE", "RDATE", "EXDATE") are
not permitted within a "VFREEBUSY" calendar component. Any recurring
events are resolved into their individual busy time periods using the
"FREEBUSY" property.
Example: The following is an example of a "VFREEBUSY" calendar
component used to request free or busy time information:
BEGIN:VFREEBUSY
ORGANIZER:MAILTO:jane_doe@host1.com
ATTENDEE:MAILTO:john_public@host2.com
DTSTART:19971015T050000Z
DTEND:19971016T050000Z
DTSTAMP:19970901T083000Z
END:VFREEBUSY
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The following is an example of a "VFREEBUSY" calendar component used
to reply to the request with busy time information:
BEGIN:VFREEBUSY
ORGANIZER:MAILTO:jane_doe@host1.com
ATTENDEE:MAILTO:john_public@host2.com
DTSTAMP:19970901T100000Z
FREEBUSY;VALUE=PERIOD:19971015T050000Z/PT8H30M,
19971015T160000Z/PT5H30M,19971015T223000Z/PT6H30M
URL:http://host2.com/pub/busy/jpublic-01.ifb
COMMENT:This iCalendar file contains busy time information for
the next three months.
END:VFREEBUSY
The following is an example of a "VFREEBUSY" calendar component used
to publish busy time information.
BEGIN:VFREEBUSY
ORGANIZER:jsmith@host.com
DTSTART:19980313T141711Z
DTEND:19980410T141711Z
FREEBUSY:19980314T233000Z/19980315T003000Z
FREEBUSY:19980316T153000Z/19980316T163000Z
FREEBUSY:19980318T030000Z/19980318T040000Z
URL:http://www.host.com/calendar/busytime/jsmith.ifb
END:VFREEBUSY
4.6.5 Time Zone Component
Component Name: VTIMEZONE
Purpose: Provide a grouping of component properties that defines a
time zone.
Formal Definition: A "VTIMEZONE" calendar component is defined by the
following notation:
timezonec = "BEGIN" ":" "VTIMEZONE" CRLF
2*(
; 'tzid' is required, but MUST NOT occur more
; than once
tzid /
; 'last-mod' and 'tzurl' are optional,
but MUST NOT occur more than once
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RFC 2445 iCalendar November 1998
last-mod / tzurl /
; one of 'standardc' or 'daylightc' MUST occur
..; and each MAY occur more than once.
standardc / daylightc /
; the following is optional,
; and MAY occur more than once
x-prop
)
"END" ":" "VTIMEZONE" CRLF
standardc = "BEGIN" ":" "STANDARD" CRLF
tzprop
"END" ":" "STANDARD" CRLF
daylightc = "BEGIN" ":" "DAYLIGHT" CRLF
tzprop
"END" ":" "DAYLIGHT" CRLF
tzprop = 3*(
; the following are each REQUIRED,
; but MUST NOT occur more than once
dtstart / tzoffsetto / tzoffsetfrom /
; the following are optional,
; and MAY occur more than once
comment / rdate / rrule / tzname / x-prop
)
Description: A time zone is unambiguously defined by the set of time
measurement rules determined by the governing body for a given
geographic area. These rules describe at a minimum the base offset
from UTC for the time zone, often referred to as the Standard Time
offset. Many locations adjust their Standard Time forward or backward
by one hour, in order to accommodate seasonal changes in number of
Dawson & Stenerson Standards Track [Page 61]
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daylight hours, often referred to as Daylight Saving Time. Some
locations adjust their time by a fraction of an hour. Standard Time
is also known as Winter Time. Daylight Saving Time is also known as
Advanced Time, Summer Time, or Legal Time in certain countries. The
following table shows the changes in time zone rules in effect for
New York City starting from 1967. Each line represents a description
or rule for a particular observance.
Effective Observance Rule
Date (Date/Time) Offset Abbreviation
1967-* last Sun in Oct, 02:00 -0500 EST
1967-1973 last Sun in Apr, 02:00 -0400 EDT
1974-1974 Jan 6, 02:00 -0400 EDT
1975-1975 Feb 23, 02:00 -0400 EDT
1976-1986 last Sun in Apr, 02:00 -0400 EDT
1987-* first Sun in Apr, 02:00 -0400 EDT
Note: The specification of a global time zone registry is not
addressed by this document and is left for future study.
However, implementers may find the Olson time zone database [TZ]
a useful reference. It is an informal, public-domain collection
of time zone information, which is currently being maintained by
volunteer Internet participants, and is used in several
operating systems. This database contains current and historical
time zone information for a wide variety of locations around the
globe; it provides a time zone identifier for every unique time
zone rule set in actual use since 1970, with historical data
going back to the introduction of standard time.
Interoperability between two calendaring and scheduling applications,
especially for recurring events, to-dos or journal entries, is
dependent on the ability to capture and convey date and time
information in an unambiguous format. The specification of current
time zone information is integral to this behavior.
If present, the "VTIMEZONE" calendar component defines the set of
Standard Time and Daylight Saving Time observances (or rules) for a
particular time zone for a given interval of time. The "VTIMEZONE"
calendar component cannot be nested within other calendar components.
Multiple "VTIMEZONE" calendar components can exist in an iCalendar
object. In this situation, each "VTIMEZONE" MUST represent a unique
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time zone definition. This is necessary for some classes of events,
such as airline flights, that start in one time zone and end in
another.
The "VTIMEZONE" calendar component MUST be present if the iCalendar
object contains an RRULE that generates dates on both sides of a time
zone shift (e.g. both in Standard Time and Daylight Saving Time)
unless the iCalendar object intends to convey a floating time (See
the section "4.1.10.11 Time" for proper interpretation of floating
time). It can be present if the iCalendar object does not contain
such a RRULE. In addition, if a RRULE is present, there MUST be valid
time zone information for all recurrence instances.
The "VTIMEZONE" calendar component MUST include the "TZID" property
and at least one definition of a standard or daylight component. The
standard or daylight component MUST include the "DTSTART",
"TZOFFSETFROM" and "TZOFFSETTO" properties.
An individual "VTIMEZONE" calendar component MUST be specified for
each unique "TZID" parameter value specified in the iCalendar object.
Each "VTIMEZONE" calendar component consists of a collection of one
or more sub-components that describe the rule for a particular
observance (either a Standard Time or a Daylight Saving Time
observance). The "STANDARD" sub-component consists of a collection of
properties that describe Standard Time. The "DAYLIGHT" sub-component
consists of a collection of properties that describe Daylight Saving
Time. In general this collection of properties consists of:
- the first onset date-time for the observance
- the last onset date-time for the observance, if a last onset
is known.
- the offset to be applied for the observance
- a rule that describes the day and time when the observance
takes effect
- an optional name for the observance
For a given time zone, there may be multiple unique definitions of
the observances over a period of time. Each observance is described
using either a "STANDARD" or "DAYLIGHT" sub-component. The collection
of these sub-components is used to describe the time zone for a given
period of time. The offset to apply at any given time is found by
locating the observance that has the last onset date and time before
the time in question, and using the offset value from that
Dawson & Stenerson Standards Track [Page 63]
RFC 2445 iCalendar November 1998
observance.
The top-level properties in a "VTIMEZONE" calendar component are:
The mandatory "TZID" property is a text value that uniquely
identifies the VTIMZONE calendar component within the scope of an
iCalendar object.
The optional "LAST-MODIFIED" property is a UTC value that specifies
the date and time that this time zone definition was last updated.
The optional "TZURL" property is url value that points to a published
VTIMEZONE definition. TZURL SHOULD refer to a resource that is
accessible by anyone who might need to interpret the object. This
SHOULD NOT normally be a file: URL or other URL that is not widely-
accessible.
The collection of properties that are used to define the STANDARD and
DAYLIGHT sub-components include:
The mandatory "DTSTART" property gives the effective onset date and
local time for the time zone sub-component definition. "DTSTART" in
this usage MUST be specified as a local DATE-TIME value.
The mandatory "TZOFFSETFROM" property gives the UTC offset which is
in use when the onset of this time zone observance begins.
"TZOFFSETFROM" is combined with "DTSTART" to define the effective
onset for the time zone sub-component definition. For example, the
following represents the time at which the observance of Standard
Time took effect in Fall 1967 for New York City:
DTSTART:19671029T020000
TZOFFSETFROM:-0400
The mandatory "TZOFFSETTO " property gives the UTC offset for the
time zone sub-component (Standard Time or Daylight Saving Time) when
this observance is in use.
The optional "TZNAME" property is the customary name for the time
zone. It may be specified multiple times, to allow for specifying
multiple language variants of the time zone names. This could be used
for displaying dates.
If specified, the onset for the observance defined by the time zone
sub-component is defined by either the "RRULE" or "RDATE" property.
If neither is specified, only one sub-component can be specified in
the "VTIMEZONE" calendar component and it is assumed that the single
Dawson & Stenerson Standards Track [Page 64]
RFC 2445 iCalendar November 1998
observance specified is always in effect.
The "RRULE" property defines the recurrence rule for the onset of the
observance defined by this time zone sub-component. Some specific
requirements for the usage of RRULE for this purpose include:
- If observance is known to have an effective end date, the
"UNTIL" recurrence rule parameter MUST be used to specify the
last valid onset of this observance (i.e., the UNTIL date-time
will be equal to the last instance generated by the recurrence
pattern). It MUST be specified in UTC time.
- The "DTSTART" and the "TZOFFSETTO" properties MUST be used
when generating the onset date-time values (instances) from the
RRULE.
Alternatively, the "RDATE" property can be used to define the onset
of the observance by giving the individual onset date and times.
"RDATE" in this usage MUST be specified as a local DATE-TIME value in
UTC time.
The optional "COMMENT" property is also allowed for descriptive
explanatory text.
Example: The following are examples of the "VTIMEZONE" calendar
component:
This is an example showing time zone information for the Eastern
United States using "RDATE" property. Note that this is only suitable
for a recurring event that starts on or later than April 6, 1997 at
03:00:00 EDT (i.e., the earliest effective transition date and time)
and ends no later than April 7, 1998 02:00:00 EST (i.e., latest valid
date and time for EST in this scenario). For example, this can be
used for a recurring event that occurs every Friday, 8am-9:00 AM,
starting June 1, 1997, ending December 31, 1997.
BEGIN:VTIMEZONE
TZID:US-Eastern
LAST-MODIFIED:19870101T000000Z
BEGIN:STANDARD
DTSTART:19971026T020000
RDATE:19971026T020000
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:19971026T020000
Dawson & Stenerson Standards Track [Page 65]
RFC 2445 iCalendar November 1998
RDATE:19970406T020000
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
END:DAYLIGHT
END:VTIMEZONE
This is a simple example showing the current time zone rules for the
Eastern United States using a RRULE recurrence pattern. Note that
there is no effective end date to either of the Standard Time or
Daylight Time rules. This information would be valid for a recurring
event starting today and continuing indefinitely.
BEGIN:VTIMEZONE
TZID:US-Eastern
LAST-MODIFIED:19870101T000000Z
TZURL:http://zones.stds_r_us.net/tz/US-Eastern
BEGIN:STANDARD
DTSTART:19671029T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:19870405T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
END:DAYLIGHT
END:VTIMEZONE
This is an example showing a fictitious set of rules for the Eastern
United States, where the Daylight Time rule has an effective end date
(i.e., after that date, Daylight Time is no longer observed).
BEGIN:VTIMEZONE
TZID:US--Fictitious-Eastern
LAST-MODIFIED:19870101T000000Z
BEGIN:STANDARD
DTSTART:19671029T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
END:STANDARD
Dawson & Stenerson Standards Track [Page 66]
RFC 2445 iCalendar November 1998
BEGIN:DAYLIGHT
DTSTART:19870405T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4;UNTIL=19980404T070000Z
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
END:DAYLIGHT
END:VTIMEZONE
This is an example showing a fictitious set of rules for the Eastern
United States, where the first Daylight Time rule has an effective
end date. There is a second Daylight Time rule that picks up where
the other left off.
BEGIN:VTIMEZONE
TZID:US--Fictitious-Eastern
LAST-MODIFIED:19870101T000000Z
BEGIN:STANDARD
DTSTART:19671029T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:19870405T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4;UNTIL=19980404T070000Z
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
END:DAYLIGHT
BEGIN:DAYLIGHT
DTSTART:19990424T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=4
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
END:DAYLIGHT
END:VTIMEZONE
4.6.6 Alarm Component
Component Name: VALARM
Purpose: Provide a grouping of component properties that define an
alarm.
Dawson & Stenerson Standards Track [Page 67]
RFC 2445 iCalendar November 1998
Formal Definition: A "VALARM" calendar component is defined by the
following notation:
alarmc = "BEGIN" ":" "VALARM" CRLF
(audioprop / dispprop / emailprop / procprop)
"END" ":" "VALARM" CRLF
audioprop = 2*(
; 'action' and 'trigger' are both REQUIRED,
; but MUST NOT occur more than once
action / trigger /
; 'duration' and 'repeat' are both optional,
; and MUST NOT occur more than once each,
; but if one occurs, so MUST the other
duration / repeat /
; the following is optional,
; but MUST NOT occur more than once
attach /
; the following is optional,
; and MAY occur more than once
x-prop
)
dispprop = 3*(
; the following are all REQUIRED,
; but MUST NOT occur more than once
action / description / trigger /
; 'duration' and 'repeat' are both optional,
; and MUST NOT occur more than once each,
; but if one occurs, so MUST the other
duration / repeat /
; the following is optional,
Dawson & Stenerson Standards Track [Page 68]
RFC 2445 iCalendar November 1998
; and MAY occur more than once
*x-prop
)
emailprop = 5*(
; the following are all REQUIRED,
; but MUST NOT occur more than once
action / description / trigger / summary
; the following is REQUIRED,
; and MAY occur more than once
attendee /
; 'duration' and 'repeat' are both optional,
; and MUST NOT occur more than once each,
; but if one occurs, so MUST the other
duration / repeat /
; the following are optional,
; and MAY occur more than once
attach / x-prop
)
procprop = 3*(
; the following are all REQUIRED,
; but MUST NOT occur more than once
action / attach / trigger /
; 'duration' and 'repeat' are both optional,
; and MUST NOT occur more than once each,
; but if one occurs, so MUST the other
duration / repeat /
Dawson & Stenerson Standards Track [Page 69]
RFC 2445 iCalendar November 1998
; 'description' is optional,
; and MUST NOT occur more than once
description /
; the following is optional,
; and MAY occur more than once
x-prop
)
Description: A "VALARM" calendar component is a grouping of component
properties that is a reminder or alarm for an event or a to-do. For
example, it may be used to define a reminder for a pending event or
an overdue to-do.
The "VALARM" calendar component MUST include the "ACTION" and
"TRIGGER" properties. The "ACTION" property further constrains the
"VALARM" calendar component in the following ways:
When the action is "AUDIO", the alarm can also include one and only
one "ATTACH" property, which MUST point to a sound resource, which is
rendered when the alarm is triggered.
When the action is "DISPLAY", the alarm MUST also include a
"DESCRIPTION" property, which contains the text to be displayed when
the alarm is triggered.
When the action is "EMAIL", the alarm MUST include a "DESCRIPTION"
property, which contains the text to be used as the message body, a
"SUMMARY" property, which contains the text to be used as the message
subject, and one or more "ATTENDEE" properties, which contain the
email address of attendees to receive the message. It can also
include one or more "ATTACH" properties, which are intended to be
sent as message attachments. When the alarm is triggered, the email
message is sent.
When the action is "PROCEDURE", the alarm MUST include one and only
one "ATTACH" property, which MUST point to a procedure resource,
which is invoked when the alarm is triggered.
The "VALARM" calendar component MUST only appear within either a
"VEVENT" or "VTODO" calendar component. "VALARM" calendar components
cannot be nested. Multiple mutually independent "VALARM" calendar
components can be specified for a single "VEVENT" or "VTODO" calendar
component.
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The "TRIGGER" property specifies when the alarm will be triggered.
The "TRIGGER" property specifies a duration prior to the start of an
event or a to-do. The "TRIGGER" edge may be explicitly set to be
relative to the "START" or "END" of the event or to-do with the
"RELATED" parameter of the "TRIGGER" property. The "TRIGGER" property
value type can alternatively be set to an absolute calendar date and
time of day value.
In an alarm set to trigger on the "START" of an event or to-do, the
"DTSTART" property MUST be present in the associated event or to-do.
In an alarm in a "VEVENT" calendar component set to trigger on the
"END" of the event, either the "DTEND" property MUST be present, or
the "DTSTART" and "DURATION" properties MUST both be present. In an
alarm in a "VTODO" calendar component set to trigger on the "END" of
the to-do, either the "DUE" property MUST be present, or the
"DTSTART" and "DURATION" properties MUST both be present.
The alarm can be defined such that it triggers repeatedly. A
definition of an alarm with a repeating trigger MUST include both the
"DURATION" and "REPEAT" properties. The "DURATION" property specifies
the delay period, after which the alarm will repeat. The "REPEAT"
property specifies the number of additional repetitions that the
alarm will triggered. This repitition count is in addition to the
initial triggering of the alarm. Both of these properties MUST be
present in order to specify a repeating alarm. If one of these two
properties is absent, then the alarm will not repeat beyond the
initial trigger.
The "ACTION" property is used within the "VALARM" calendar component
to specify the type of action invoked when the alarm is triggered.
The "VALARM" properties provide enough information for a specific
action to be invoked. It is typically the responsibility of a
"Calendar User Agent" (CUA) to deliver the alarm in the specified
fashion. An "ACTION" property value of AUDIO specifies an alarm that
causes a sound to be played to alert the user; DISPLAY specifies an
alarm that causes a text message to be displayed to the user; EMAIL
specifies an alarm that causes an electronic email message to be
delivered to one or more email addresses; and PROCEDURE specifies an
alarm that causes a procedure to be executed. The "ACTION" property
MUST specify one and only one of these values.
In an AUDIO alarm, if the optional "ATTACH" property is included, it
MUST specify an audio sound resource. The intention is that the sound
will be played as the alarm effect. If an "ATTACH" property is
specified that does not refer to a sound resource, or if the
specified sound resource cannot be rendered (because its format is
unsupported, or because it cannot be retrieved), then the CUA or
other entity responsible for playing the sound may choose a fallback
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action, such as playing a built-in default sound, or playing no sound
at all.
In a DISPLAY alarm, the intended alarm effect is for the text value
of the "DESCRIPTION" property to be displayed to the user.
In an EMAIL alarm, the intended alarm effect is for an email message
to be composed and delivered to all the addresses specified by the
"ATTENDEE" properties in the "VALARM" calendar component. The
"DESCRIPTION" property of the "VALARM" calendar component MUST be
used as the body text of the message, and the "SUMMARY" property MUST
be used as the subject text. Any "ATTACH" properties in the "VALARM"
calendar component SHOULD be sent as attachments to the message.
In a PROCEDURE alarm, the "ATTACH" property in the "VALARM" calendar
component MUST specify a procedure or program that is intended to be
invoked as the alarm effect. If the procedure or program is in a
format that cannot be rendered, then no procedure alarm will be
invoked. If the "DESCRIPTION" property is present, its value
specifies the argument string to be passed to the procedure or
program. "Calendar User Agents" that receive an iCalendar object with
this category of alarm, can disable or allow the "Calendar User" to
disable, or otherwise ignore this type of alarm. While a very useful
alarm capability, the PROCEDURE type of alarm SHOULD be treated by
the "Calendar User Agent" as a potential security risk.
Example: The following example is for a "VALARM" calendar component
that specifies an audio alarm that will sound at a precise time and
repeat 4 more times at 15 minute intervals:
BEGIN:VALARM
TRIGGER;VALUE=DATE-TIME:19970317T133000Z
REPEAT:4
DURATION:PT15M
ACTION:AUDIO
ATTACH;FMTTYPE=audio/basic:ftp://host.com/pub/sounds/bell-01.aud
END:VALARM
The following example is for a "VALARM" calendar component that
specifies a display alarm that will trigger 30 minutes before the
scheduled start of the event or the due date/time of the to-do it is
associated with and will repeat 2 more times at 15 minute intervals:
BEGIN:VALARM
TRIGGER:-PT30M
REPEAT:2
DURATION:PT15M
ACTION:DISPLAY
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DESCRIPTION:Breakfast meeting with executive\n
team at 8:30 AM EST.
END:VALARM
The following example is for a "VALARM" calendar component that
specifies an email alarm that will trigger 2 days before the
scheduled due date/time of a to-do it is associated with. It does not
repeat. The email has a subject, body and attachment link.
BEGIN:VALARM
TRIGGER:-P2D
ACTION:EMAIL
ATTENDEE:MAILTO:john_doe@host.com
SUMMARY:*** REMINDER: SEND AGENDA FOR WEEKLY STAFF MEETING ***
DESCRIPTION:A draft agenda needs to be sent out to the attendees
to the weekly managers meeting (MGR-LIST). Attached is a
pointer the document template for the agenda file.
ATTACH;FMTTYPE=application/binary:http://host.com/templates/agen
da.doc
END:VALARM
The following example is for a "VALARM" calendar component that
specifies a procedural alarm that will trigger at a precise date/time
and will repeat 23 more times at one hour intervals. The alarm will
invoke a procedure file.
BEGIN:VALARM
TRIGGER;VALUE=DATE-TIME:19980101T050000Z
REPEAT:23
DURATION:PT1H
ACTION:PROCEDURE
ATTACH;FMTTYPE=application/binary:ftp://host.com/novo-
procs/felizano.exe
END:VALARM
4.7 Calendar Properties
The Calendar Properties are attributes that apply to the iCalendar
object, as a whole. These properties do not appear within a calendar
component. They SHOULD be specified after the "BEGIN:VCALENDAR"
property and prior to any calendar component.
4.7.1 Calendar Scale
Property Name: CALSCALE
Purpose: This property defines the calendar scale used for the
calendar information specified in the iCalendar object.
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Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: Property can be specified in an iCalendar object. The
default value is "GREGORIAN".
Description: This memo is based on the Gregorian calendar scale. The
Gregorian calendar scale is assumed if this property is not specified
in the iCalendar object. It is expected that other calendar scales
will be defined in other specifications or by future versions of this
memo.
Format Definition: The property is defined by the following notation:
calscale = "CALSCALE" calparam ":" calvalue CRLF
calparam = *(";" xparam)
calvalue = "GREGORIAN" / iana-token
Example: The following is an example of this property:
CALSCALE:GREGORIAN
4.7.2 Method
Property Name: METHOD
Purpose: This property defines the iCalendar object method associated
with the calendar object.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property can be specified in an iCalendar object.
Description: When used in a MIME message entity, the value of this
property MUST be the same as the Content-Type "method" parameter
value. This property can only appear once within the iCalendar
object. If either the "METHOD" property or the Content-Type "method"
parameter is specified, then the other MUST also be specified.
No methods are defined by this specification. This is the subject of
other specifications, such as the iCalendar Transport-independent
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Interoperability Protocol (iTIP) defined by [ITIP].
If this property is not present in the iCalendar object, then a
scheduling transaction MUST NOT be assumed. In such cases, the
iCalendar object is merely being used to transport a snapshot of some
calendar information; without the intention of conveying a scheduling
semantic.
Format Definition: The property is defined by the following notation:
method = "METHOD" metparam ":" metvalue CRLF
metparam = *(";" xparam)
metvalue = iana-token
Example: The following is a hypothetical example of this property to
convey that the iCalendar object is a request for a meeting:
METHOD:REQUEST
4.7.3 Product Identifier
Property Name: PRODID
Purpose: This property specifies the identifier for the product that
created the iCalendar object.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property MUST be specified once in an iCalendar
object.
Description: The vendor of the implementation SHOULD assure that this
is a globally unique identifier; using some technique such as an FPI
value, as defined in [ISO 9070].
This property SHOULD not be used to alter the interpretation of an
iCalendar object beyond the semantics specified in this memo. For
example, it is not to be used to further the understanding of non-
standard properties.
Format Definition: The property is defined by the following notation:
prodid = "PRODID" pidparam ":" pidvalue CRLF
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pidparam = *(";" xparam)
pidvalue = text
;Any text that describes the product and version
;and that is generally assured of being unique.
Example: The following is an example of this property. It does not
imply that English is the default language.
PRODID:-//ABC Corporation//NONSGML My Product//EN
4.7.4 Version
Property Name: VERSION
Purpose: This property specifies the identifier corresponding to the
highest version number or the minimum and maximum range of the
iCalendar specification that is required in order to interpret the
iCalendar object.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property MUST be specified by an iCalendar object,
but MUST only be specified once.
Description: A value of "2.0" corresponds to this memo.
Format Definition: The property is defined by the following notation:
version = "VERSION" verparam ":" vervalue CRLF
verparam = *(";" xparam)
vervalue = "2.0" ;This memo
/ maxver
/ (minver ";" maxver)
minver = <A IANA registered iCalendar version identifier>
;Minimum iCalendar version needed to parse the iCalendar object
maxver = <A IANA registered iCalendar version identifier>
;Maximum iCalendar version needed to parse the iCalendar object
Example: The following is an example of this property:
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VERSION:2.0
4.8 Component Properties
The following properties can appear within calendar components, as
specified by each component property definition.
4.8.1 Descriptive Component Properties
The following properties specify descriptive information about
calendar components.
4.8.1.1 Attachment
Property Name: ATTACH
Purpose: The property provides the capability to associate a document
object with a calendar component.
Value Type: The default value type for this property is URI. The
value type can also be set to BINARY to indicate inline binary
encoded content information.
Property Parameters: Non-standard, inline encoding, format type and
value data type property parameters can be specified on this
property.
Conformance: The property can be specified in a "VEVENT", "VTODO",
"VJOURNAL" or "VALARM" calendar components.
Description: The property can be specified within "VEVENT", "VTODO",
"VJOURNAL", or "VALARM" calendar components. This property can be
specified multiple times within an iCalendar object.
Format Definition: The property is defined by the following notation:
attach = "ATTACH" attparam ":" uri CRLF
attach =/ "ATTACH" attparam ";" "ENCODING" "=" "BASE64"
";" "VALUE" "=" "BINARY" ":" binary
attparam = *(
; the following is optional,
; but MUST NOT occur more than once
(";" fmttypeparam) /
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; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following are examples of this property:
ATTACH:CID:jsmith.part3.960817T083000.xyzMail@host1.com
ATTACH;FMTTYPE=application/postscript:ftp://xyzCorp.com/pub/
reports/r-960812.ps
4.8.1.2 Categories
Property Name: CATEGORIES
Purpose: This property defines the categories for a calendar
component.
Value Type: TEXT
Property Parameters: Non-standard and language property parameters
can be specified on this property.
Conformance: The property can be specified within "VEVENT", "VTODO"
or "VJOURNAL" calendar components.
Description: This property is used to specify categories or subtypes
of the calendar component. The categories are useful in searching for
a calendar component of a particular type and category. Within the
"VEVENT", "VTODO" or "VJOURNAL" calendar components, more than one
category can be specified as a list of categories separated by the
COMMA character (US-ASCII decimal 44).
Format Definition: The property is defined by the following notation:
categories = "CATEGORIES" catparam ":" text *("," text)
CRLF
catparam = *(
; the following is optional,
; but MUST NOT occur more than once
(";" languageparam ) /
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; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following are examples of this property:
CATEGORIES:APPOINTMENT,EDUCATION
CATEGORIES:MEETING
4.8.1.3 Classification
Property Name: CLASS
Purpose: This property defines the access classification for a
calendar component.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property can be specified once in a "VEVENT",
"VTODO" or "VJOURNAL" calendar components.
Description: An access classification is only one component of the
general security system within a calendar application. It provides a
method of capturing the scope of the access the calendar owner
intends for information within an individual calendar entry. The
access classification of an individual iCalendar component is useful
when measured along with the other security components of a calendar
system (e.g., calendar user authentication, authorization, access
rights, access role, etc.). Hence, the semantics of the individual
access classifications cannot be completely defined by this memo
alone. Additionally, due to the "blind" nature of most exchange
processes using this memo, these access classifications cannot serve
as an enforcement statement for a system receiving an iCalendar
object. Rather, they provide a method for capturing the intention of
the calendar owner for the access to the calendar component.
Format Definition: The property is defined by the following notation:
class = "CLASS" classparam ":" classvalue CRLF
classparam = *(";" xparam)
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classvalue = "PUBLIC" / "PRIVATE" / "CONFIDENTIAL" / iana-token
/ x-name
;Default is PUBLIC
Example: The following is an example of this property:
CLASS:PUBLIC
4.8.1.4 Comment
Property Name: COMMENT
Purpose: This property specifies non-processing information intended
to provide a comment to the calendar user.
Value Type: TEXT
Property Parameters: Non-standard, alternate text representation and
language property parameters can be specified on this property.
Conformance: This property can be specified in "VEVENT", "VTODO",
"VJOURNAL", "VTIMEZONE" or "VFREEBUSY" calendar components.
Description: The property can be specified multiple times.
Format Definition: The property is defined by the following notation:
comment = "COMMENT" commparam ":" text CRLF
commparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" altrepparam) / (";" languageparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following is an example of this property:
COMMENT:The meeting really needs to include both ourselves
and the customer. We can't hold this meeting without them.
As a matter of fact\, the venue for the meeting ought to be at
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their site. - - John
The data type for this property is TEXT.
4.8.1.5 Description
Property Name: DESCRIPTION
Purpose: This property provides a more complete description of the
calendar component, than that provided by the "SUMMARY" property.
Value Type: TEXT
Property Parameters: Non-standard, alternate text representation and
language property parameters can be specified on this property.
Conformance: The property can be specified in the "VEVENT", "VTODO",
"VJOURNAL" or "VALARM" calendar components. The property can be
specified multiple times only within a "VJOURNAL" calendar component.
Description: This property is used in the "VEVENT" and "VTODO" to
capture lengthy textual decriptions associated with the activity.
This property is used in the "VJOURNAL" calendar component to capture
one more textual journal entries.
This property is used in the "VALARM" calendar component to capture
the display text for a DISPLAY category of alarm, to capture the body
text for an EMAIL category of alarm and to capture the argument
string for a PROCEDURE category of alarm.
Format Definition: The property is defined by the following notation:
description = "DESCRIPTION" descparam ":" text CRLF
descparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" altrepparam) / (";" languageparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
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Example: The following is an example of the property with formatted
line breaks in the property value:
DESCRIPTION:Meeting to provide technical review for "Phoenix"
design.\n Happy Face Conference Room. Phoenix design team
MUST attend this meeting.\n RSVP to team leader.
The following is an example of the property with folding of long
lines:
DESCRIPTION:Last draft of the new novel is to be completed
for the editor's proof today.
4.8.1.6 Geographic Position
Property Name: GEO
Purpose: This property specifies information related to the global
position for the activity specified by a calendar component.
Value Type: FLOAT. The value MUST be two SEMICOLON separated FLOAT
values.
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified in "VEVENT" or "VTODO"
calendar components.
Description: The property value specifies latitude and longitude, in
that order (i.e., "LAT LON" ordering). The longitude represents the
location east or west of the prime meridian as a positive or negative
real number, respectively. The longitude and latitude values MAY be
specified up to six decimal places, which will allow for accuracy to
within one meter of geographical position. Receiving applications
MUST accept values of this precision and MAY truncate values of
greater precision.
Values for latitude and longitude shall be expressed as decimal
fractions of degrees. Whole degrees of latitude shall be represented
by a two-digit decimal number ranging from 0 through 90. Whole
degrees of longitude shall be represented by a decimal number ranging
from 0 through 180. When a decimal fraction of a degree is specified,
it shall be separated from the whole number of degrees by a decimal
point.
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Latitudes north of the equator shall be specified by a plus sign (+),
or by the absence of a minus sign (-), preceding the digits
designating degrees. Latitudes south of the Equator shall be
designated by a minus sign (-) preceding the digits designating
degrees. A point on the Equator shall be assigned to the Northern
Hemisphere.
Longitudes east of the prime meridian shall be specified by a plus
sign (+), or by the absence of a minus sign (-), preceding the digits
designating degrees. Longitudes west of the meridian shall be
designated by minus sign (-) preceding the digits designating
degrees. A point on the prime meridian shall be assigned to the
Eastern Hemisphere. A point on the 180th meridian shall be assigned
to the Western Hemisphere. One exception to this last convention is
permitted. For the special condition of describing a band of latitude
around the earth, the East Bounding Coordinate data element shall be
assigned the value +180 (180) degrees.
Any spatial address with a latitude of +90 (90) or -90 degrees will
specify the position at the North or South Pole, respectively. The
component for longitude may have any legal value.
With the exception of the special condition described above, this
form is specified in Department of Commerce, 1986, Representation of
geographic point locations for information interchange (Federal
Information Processing Standard 70-1): Washington, Department of
Commerce, National Institute of Standards and Technology.
The simple formula for converting degrees-minutes-seconds into
decimal degrees is:
decimal = degrees + minutes/60 + seconds/3600.
Format Definition: The property is defined by the following notation:
geo = "GEO" geoparam ":" geovalue CRLF
geoparam = *(";" xparam)
geovalue = float ";" float
;Latitude and Longitude components
Example: The following is an example of this property:
GEO:37.386013;-122.082932
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4.8.1.7 Location
Property Name: LOCATION
Purpose: The property defines the intended venue for the activity
defined by a calendar component.
Value Type: TEXT
Property Parameters: Non-standard, alternate text representation and
language property parameters can be specified on this property.
Conformance: This property can be specified in "VEVENT" or "VTODO"
calendar component.
Description: Specific venues such as conference or meeting rooms may
be explicitly specified using this property. An alternate
representation may be specified that is a URI that points to
directory information with more structured specification of the
location. For example, the alternate representation may specify
either an LDAP URI pointing to an LDAP server entry or a CID URI
pointing to a MIME body part containing a vCard [RFC 2426] for the
location.
Format Definition: The property is defined by the following notation:
location = "LOCATION locparam ":" text CRLF
locparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" altrepparam) / (";" languageparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following are some examples of this property:
LOCATION:Conference Room - F123, Bldg. 002
LOCATION;ALTREP="http://xyzcorp.com/conf-rooms/f123.vcf":
Conference Room - F123, Bldg. 002
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4.8.1.8 Percent Complete
Property Name: PERCENT-COMPLETE
Purpose: This property is used by an assignee or delegatee of a to-do
to convey the percent completion of a to-do to the Organizer.
Value Type: INTEGER
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified in a "VTODO" calendar
component.
Description: The property value is a positive integer between zero
and one hundred. A value of "0" indicates the to-do has not yet been
started. A value of "100" indicates that the to-do has been
completed. Integer values in between indicate the percent partially
complete.
When a to-do is assigned to multiple individuals, the property value
indicates the percent complete for that portion of the to-do assigned
to the assignee or delegatee. For example, if a to-do is assigned to
both individuals "A" and "B". A reply from "A" with a percent
complete of "70" indicates that "A" has completed 70% of the to-do
assigned to them. A reply from "B" with a percent complete of "50"
indicates "B" has completed 50% of the to-do assigned to them.
Format Definition: The property is defined by the following notation:
percent = "PERCENT-COMPLETE" pctparam ":" integer CRLF
pctparam = *(";" xparam)
Example: The following is an example of this property to show 39%
completion:
PERCENT-COMPLETE:39
4.8.1.9 Priority
Property Name: PRIORITY
Purpose: The property defines the relative priority for a calendar
component.
Value Type: INTEGER
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Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property can be specified in a "VEVENT" or "VTODO"
calendar component.
Description: The priority is specified as an integer in the range
zero to nine. A value of zero (US-ASCII decimal 48) specifies an
undefined priority. A value of one (US-ASCII decimal 49) is the
highest priority. A value of two (US-ASCII decimal 50) is the second
highest priority. Subsequent numbers specify a decreasing ordinal
priority. A value of nine (US-ASCII decimal 58) is the lowest
priority.
A CUA with a three-level priority scheme of "HIGH", "MEDIUM" and
"LOW" is mapped into this property such that a property value in the
range of one (US-ASCII decimal 49) to four (US-ASCII decimal 52)
specifies "HIGH" priority. A value of five (US-ASCII decimal 53) is
the normal or "MEDIUM" priority. A value in the range of six (US-
ASCII decimal 54) to nine (US-ASCII decimal 58) is "LOW" priority.
A CUA with a priority schema of "A1", "A2", "A3", "B1", "B2", ...,
"C3" is mapped into this property such that a property value of one
(US-ASCII decimal 49) specifies "A1", a property value of two (US-
ASCII decimal 50) specifies "A2", a property value of three (US-ASCII
decimal 51) specifies "A3", and so forth up to a property value of 9
(US-ASCII decimal 58) specifies "C3".
Other integer values are reserved for future use.
Within a "VEVENT" calendar component, this property specifies a
priority for the event. This property may be useful when more than
one event is scheduled for a given time period.
Within a "VTODO" calendar component, this property specified a
priority for the to-do. This property is useful in prioritizing
multiple action items for a given time period.
Format Definition: The property is specified by the following
notation:
priority = "PRIORITY" prioparam ":" privalue CRLF
;Default is zero
prioparam = *(";" xparam)
privalue = integer ;Must be in the range [0..9]
; All other values are reserved for future use
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The following is an example of a property with the highest priority:
PRIORITY:1
The following is an example of a property with a next highest
priority:
PRIORITY:2
Example: The following is an example of a property with no priority.
This is equivalent to not specifying the "PRIORITY" property:
PRIORITY:0
4.8.1.10 Resources
Property Name: RESOURCES
Purpose: This property defines the equipment or resources anticipated
for an activity specified by a calendar entity..
Value Type: TEXT
Property Parameters: Non-standard, alternate text representation and
language property parameters can be specified on this property.
Conformance: This property can be specified in "VEVENT" or "VTODO"
calendar component.
Description: The property value is an arbitrary text. More than one
resource can be specified as a list of resources separated by the
COMMA character (US-ASCII decimal 44).
Format Definition: The property is defined by the following notation:
resources = "RESOURCES" resrcparam ":" text *("," text) CRLF
resrcparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" altrepparam) / (";" languageparam) /
; the following is optional,
; and MAY occur more than once
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(";" xparam)
)
Example: The following is an example of this property:
RESOURCES:EASEL,PROJECTOR,VCR
RESOURCES;LANGUAGE=fr:1 raton-laveur
4.8.1.11 Status
Property Name: STATUS
Purpose: This property defines the overall status or confirmation for
the calendar component.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified in "VEVENT", "VTODO" or
"VJOURNAL" calendar components.
Description: In a group scheduled calendar component, the property is
used by the "Organizer" to provide a confirmation of the event to the
"Attendees". For example in a "VEVENT" calendar component, the
"Organizer" can indicate that a meeting is tentative, confirmed or
cancelled. In a "VTODO" calendar component, the "Organizer" can
indicate that an action item needs action, is completed, is in
process or being worked on, or has been cancelled. In a "VJOURNAL"
calendar component, the "Organizer" can indicate that a journal entry
is draft, final or has been cancelled or removed.
Format Definition: The property is defined by the following notation:
status = "STATUS" statparam] ":" statvalue CRLF
statparam = *(";" xparam)
statvalue = "TENTATIVE" ;Indicates event is
;tentative.
/ "CONFIRMED" ;Indicates event is
;definite.
/ "CANCELLED" ;Indicates event was
;cancelled.
;Status values for a "VEVENT"
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statvalue =/ "NEEDS-ACTION" ;Indicates to-do needs action.
/ "COMPLETED" ;Indicates to-do completed.
/ "IN-PROCESS" ;Indicates to-do in process of
/ "CANCELLED" ;Indicates to-do was cancelled.
;Status values for "VTODO".
statvalue =/ "DRAFT" ;Indicates journal is draft.
/ "FINAL" ;Indicates journal is final.
/ "CANCELLED" ;Indicates journal is removed.
;Status values for "VJOURNAL".
Example: The following is an example of this property for a "VEVENT"
calendar component:
STATUS:TENTATIVE
The following is an example of this property for a "VTODO" calendar
component:
STATUS:NEEDS-ACTION
The following is an example of this property for a "VJOURNAL"
calendar component:
STATUS:DRAFT
4.8.1.12 Summary
Property Name: SUMMARY
Purpose: This property defines a short summary or subject for the
calendar component.
Value Type: TEXT
Property Parameters: Non-standard, alternate text representation and
language property parameters can be specified on this property.
Conformance: The property can be specified in "VEVENT", "VTODO",
"VJOURNAL" or "VALARM" calendar components.
Description: This property is used in the "VEVENT", "VTODO" and
"VJOURNAL" calendar components to capture a short, one line summary
about the activity or journal entry.
This property is used in the "VALARM" calendar component to capture
the subject of an EMAIL category of alarm.
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Format Definition: The property is defined by the following notation:
summary = "SUMMARY" summparam ":" text CRLF
summparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" altrepparam) / (";" languageparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following is an example of this property:
SUMMARY:Department Party
4.8.2 Date and Time Component Properties
The following properties specify date and time related information in
calendar components.
4.8.2.1 Date/Time Completed
Property Name: COMPLETED
Purpose: This property defines the date and time that a to-do was
actually completed.
Value Type: DATE-TIME
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property can be specified in a "VTODO" calendar
component.
Description: The date and time MUST be in a UTC format.
Format Definition: The property is defined by the following notation:
completed = "COMPLETED" compparam ":" date-time CRLF
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compparam = *(";" xparam)
Example: The following is an example of this property:
COMPLETED:19960401T235959Z
4.8.2.2 Date/Time End
Property Name: DTEND
Purpose: This property specifies the date and time that a calendar
component ends.
Value Type: The default value type is DATE-TIME. The value type can
be set to a DATE value type.
Property Parameters: Non-standard, value data type, time zone
identifier property parameters can be specified on this property.
Conformance: This property can be specified in "VEVENT" or
"VFREEBUSY" calendar components.
Description: Within the "VEVENT" calendar component, this property
defines the date and time by which the event ends. The value MUST be
later in time than the value of the "DTSTART" property.
Within the "VFREEBUSY" calendar component, this property defines the
end date and time for the free or busy time information. The time
MUST be specified in the UTC time format. The value MUST be later in
time than the value of the "DTSTART" property.
Format Definition: The property is defined by the following notation:
dtend = "DTEND" dtendparam":" dtendval CRLF
dtendparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
(";" tzidparam) /
; the following is optional,
; and MAY occur more than once
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(";" xparam)
)
dtendval = date-time / date
;Value MUST match value type
Example: The following is an example of this property:
DTEND:19960401T235959Z
DTEND;VALUE=DATE:19980704
4.8.2.3 Date/Time Due
Property Name: DUE
Purpose: This property defines the date and time that a to-do is
expected to be completed.
Value Type: The default value type is DATE-TIME. The value type can
be set to a DATE value type.
Property Parameters: Non-standard, value data type, time zone
identifier property parameters can be specified on this property.
Conformance: The property can be specified once in a "VTODO" calendar
component.
Description: The value MUST be a date/time equal to or after the
DTSTART value, if specified.
Format Definition: The property is defined by the following notation:
due = "DUE" dueparam":" dueval CRLF
dueparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
(";" tzidparam) /
; the following is optional,
; and MAY occur more than once
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*(";" xparam)
)
dueval = date-time / date
;Value MUST match value type
Example: The following is an example of this property:
DUE:19980430T235959Z
4.8.2.4 Date/Time Start
Property Name: DTSTART
Purpose: This property specifies when the calendar component begins.
Value Type: The default value type is DATE-TIME. The time value MUST
be one of the forms defined for the DATE-TIME value type. The value
type can be set to a DATE value type.
Property Parameters: Non-standard, value data type, time zone
identifier property parameters can be specified on this property.
Conformance: This property can be specified in the "VEVENT", "VTODO",
"VFREEBUSY", or "VTIMEZONE" calendar components.
Description: Within the "VEVENT" calendar component, this property
defines the start date and time for the event. The property is
REQUIRED in "VEVENT" calendar components. Events can have a start
date/time but no end date/time. In that case, the event does not take
up any time.
Within the "VFREEBUSY" calendar component, this property defines the
start date and time for the free or busy time information. The time
MUST be specified in UTC time.
Within the "VTIMEZONE" calendar component, this property defines the
effective start date and time for a time zone specification. This
property is REQUIRED within each STANDARD and DAYLIGHT part included
in "VTIMEZONE" calendar components and MUST be specified as a local
DATE-TIME without the "TZID" property parameter.
Format Definition: The property is defined by the following notation:
dtstart = "DTSTART" dtstparam ":" dtstval CRLF
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dtstparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
(";" tzidparam) /
; the following is optional,
; and MAY occur more than once
*(";" xparam)
)
dtstval = date-time / date
;Value MUST match value type
Example: The following is an example of this property:
DTSTART:19980118T073000Z
4.8.2.5 Duration
Property Name: DURATION
Purpose: The property specifies a positive duration of time.
Value Type: DURATION
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property can be specified in "VEVENT", "VTODO",
"VFREEBUSY" or "VALARM" calendar components.
Description: In a "VEVENT" calendar component the property may be
used to specify a duration of the event, instead of an explicit end
date/time. In a "VTODO" calendar component the property may be used
to specify a duration for the to-do, instead of an explicit due
date/time. In a "VFREEBUSY" calendar component the property may be
used to specify the interval of free time being requested. In a
"VALARM" calendar component the property may be used to specify the
delay period prior to repeating an alarm.
Format Definition: The property is defined by the following notation:
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duration = "DURATION" durparam ":" dur-value CRLF
;consisting of a positive duration of time.
durparam = *(";" xparam)
Example: The following is an example of this property that specifies
an interval of time of 1 hour and zero minutes and zero seconds:
DURATION:PT1H0M0S
The following is an example of this property that specifies an
interval of time of 15 minutes.
DURATION:PT15M
4.8.2.6 Free/Busy Time
Property Name: FREEBUSY
Purpose: The property defines one or more free or busy time
intervals.
Value Type: PERIOD. The date and time values MUST be in an UTC time
format.
Property Parameters: Non-standard or free/busy time type property
parameters can be specified on this property.
Conformance: The property can be specified in a "VFREEBUSY" calendar
component.
Property Parameter: "FBTYPE" and non-standard parameters can be
specified on this property.
Description: These time periods can be specified as either a start
and end date-time or a start date-time and duration. The date and
time MUST be a UTC time format.
"FREEBUSY" properties within the "VFREEBUSY" calendar component
SHOULD be sorted in ascending order, based on start time and then end
time, with the earliest periods first.
The "FREEBUSY" property can specify more than one value, separated by
the COMMA character (US-ASCII decimal 44). In such cases, the
"FREEBUSY" property values SHOULD all be of the same "FBTYPE"
property parameter type (e.g., all values of a particular "FBTYPE"
listed together in a single property).
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Format Definition: The property is defined by the following notation:
freebusy = "FREEBUSY" fbparam ":" fbvalue
CRLF
fbparam = *(
; the following is optional,
; but MUST NOT occur more than once
(";" fbtypeparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
fbvalue = period *["," period]
;Time value MUST be in the UTC time format.
Example: The following are some examples of this property:
FREEBUSY;FBTYPE=BUSY-UNAVAILABLE:19970308T160000Z/PT8H30M
FREEBUSY;FBTYPE=FREE:19970308T160000Z/PT3H,19970308T200000Z/PT1H
FREEBUSY;FBTYPE=FREE:19970308T160000Z/PT3H,19970308T200000Z/PT1H,
19970308T230000Z/19970309T000000Z
4.8.2.7 Time Transparency
Property Name: TRANSP
Purpose: This property defines whether an event is transparent or not
to busy time searches.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified once in a "VEVENT"
calendar component.
Description: Time Transparency is the characteristic of an event that
determines whether it appears to consume time on a calendar. Events
that consume actual time for the individual or resource associated
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with the calendar SHOULD be recorded as OPAQUE, allowing them to be
detected by free-busy time searches. Other events, which do not take
up the individual's (or resource's) time SHOULD be recorded as
TRANSPARENT, making them invisible to free-busy time searches.
Format Definition: The property is specified by the following
notation:
transp = "TRANSP" tranparam ":" transvalue CRLF
tranparam = *(";" xparam)
transvalue = "OPAQUE" ;Blocks or opaque on busy time searches.
/ "TRANSPARENT" ;Transparent on busy time searches.
;Default value is OPAQUE
Example: The following is an example of this property for an event
that is transparent or does not block on free/busy time searches:
TRANSP:TRANSPARENT
The following is an example of this property for an event that is
opaque or blocks on free/busy time searches:
TRANSP:OPAQUE
4.8.3 Time Zone Component Properties
The following properties specify time zone information in calendar
components.
4.8.3.1 Time Zone Identifier
Property Name: TZID
Purpose: This property specifies the text value that uniquely
identifies the "VTIMEZONE" calendar component.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property MUST be specified in a "VTIMEZONE"
calendar component.
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Description: This is the label by which a time zone calendar
component is referenced by any iCalendar properties whose data type
is either DATE-TIME or TIME and not intended to specify a UTC or a
"floating" time. The presence of the SOLIDUS character (US-ASCII
decimal 47) as a prefix, indicates that this TZID represents an
unique ID in a globally defined time zone registry (when such
registry is defined).
Note: This document does not define a naming convention for time
zone identifiers. Implementers may want to use the naming
conventions defined in existing time zone specifications such as
the public-domain Olson database [TZ]. The specification of
globally unique time zone identifiers is not addressed by this
document and is left for future study.
Format Definition: This property is defined by the following
notation:
tzid = "TZID" tzidpropparam ":" [tzidprefix] text CRLF
tzidpropparam = *(";" xparam)
;tzidprefix = "/"
; Defined previously. Just listed here for reader convenience.
Example: The following are examples of non-globally unique time zone
identifiers:
TZID:US-Eastern
TZID:California-Los_Angeles
The following is an example of a fictitious globally unique time zone
identifier:
TZID:/US-New_York-New_York
4.8.3.2 Time Zone Name
Property Name: TZNAME
Purpose: This property specifies the customary designation for a time
zone description.
Value Type: TEXT
Property Parameters: Non-standard and language property parameters
can be specified on this property.
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Conformance: This property can be specified in a "VTIMEZONE" calendar
component.
Description: This property may be specified in multiple languages; in
order to provide for different language requirements.
Format Definition: This property is defined by the following
notation:
tzname = "TZNAME" tznparam ":" text CRLF
tznparam = *(
; the following is optional,
; but MUST NOT occur more than once
(";" languageparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following are example of this property:
TZNAME:EST
The following is an example of this property when two different
languages for the time zone name are specified:
TZNAME;LANGUAGE=en:EST
TZNAME;LANGUAGE=fr-CA:HNE
4.8.3.3 Time Zone Offset From
Property Name: TZOFFSETFROM
Purpose: This property specifies the offset which is in use prior to
this time zone observance.
Value Type: UTC-OFFSET
Property Parameters: Non-standard property parameters can be
specified on this property.
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Conformance: This property MUST be specified in a "VTIMEZONE"
calendar component.
Description: This property specifies the offset which is in use prior
to this time observance. It is used to calculate the absolute time at
which the transition to a given observance takes place. This property
MUST only be specified in a "VTIMEZONE" calendar component. A
"VTIMEZONE" calendar component MUST include this property. The
property value is a signed numeric indicating the number of hours and
possibly minutes from UTC. Positive numbers represent time zones east
of the prime meridian, or ahead of UTC. Negative numbers represent
time zones west of the prime meridian, or behind UTC.
Format Definition: The property is defined by the following notation:
tzoffsetfrom = "TZOFFSETFROM" frmparam ":" utc-offset
CRLF
frmparam = *(";" xparam)
Example: The following are examples of this property:
TZOFFSETFROM:-0500
TZOFFSETFROM:+1345
4.8.3.4 Time Zone Offset To
Property Name: TZOFFSETTO
Purpose: This property specifies the offset which is in use in this
time zone observance.
Value Type: UTC-OFFSET
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property MUST be specified in a "VTIMEZONE"
calendar component.
Description: This property specifies the offset which is in use in
this time zone observance. It is used to calculate the absolute time
for the new observance. The property value is a signed numeric
indicating the number of hours and possibly minutes from UTC.
Positive numbers represent time zones east of the prime meridian, or
ahead of UTC. Negative numbers represent time zones west of the prime
meridian, or behind UTC.
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Format Definition: The property is defined by the following notation:
tzoffsetto = "TZOFFSETTO" toparam ":" utc-offset CRLF
toparam = *(";" xparam)
Example: The following are examples of this property:
TZOFFSETTO:-0400
TZOFFSETTO:+1245
4.8.3.5 Time Zone URL
Property Name: TZURL
Purpose: The TZURL provides a means for a VTIMEZONE component to
point to a network location that can be used to retrieve an up-to-
date version of itself.
Value Type: URI
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified in a "VTIMEZONE" calendar
component.
Description: The TZURL provides a means for a VTIMEZONE component to
point to a network location that can be used to retrieve an up-to-
date version of itself. This provides a hook to handle changes
government bodies impose upon time zone definitions. Retrieval of
this resource results in an iCalendar object containing a single
VTIMEZONE component and a METHOD property set to PUBLISH.
Format Definition: The property is defined by the following notation:
tzurl = "TZURL" tzurlparam ":" uri CRLF
tzurlparam = *(";" xparam)
Example: The following is an example of this property:
TZURL:http://timezones.r.us.net/tz/US-California-Los_Angeles
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4.8.4 Relationship Component Properties
The following properties specify relationship information in calendar
components.
4.8.4.1 Attendee
Property Name: ATTENDEE
Purpose: The property defines an "Attendee" within a calendar
component.
Value Type: CAL-ADDRESS
Property Parameters: Non-standard, language, calendar user type,
group or list membership, participation role, participation status,
RSVP expectation, delegatee, delegator, sent by, common name or
directory entry reference property parameters can be specified on
this property.
Conformance: This property MUST be specified in an iCalendar object
that specifies a group scheduled calendar entity. This property MUST
NOT be specified in an iCalendar object when publishing the calendar
information (e.g., NOT in an iCalendar object that specifies the
publication of a calendar user's busy time, event, to-do or journal).
This property is not specified in an iCalendar object that specifies
only a time zone definition or that defines calendar entities that
are not group scheduled entities, but are entities only on a single
user's calendar.
Description: The property MUST only be specified within calendar
components to specify participants, non-participants and the chair of
a group scheduled calendar entity. The property is specified within
an "EMAIL" category of the "VALARM" calendar component to specify an
email address that is to receive the email type of iCalendar alarm.
The property parameter CN is for the common or displayable name
associated with the calendar address; ROLE, for the intended role
that the attendee will have in the calendar component; PARTSTAT, for
the status of the attendee's participation; RSVP, for indicating
whether the favor of a reply is requested; CUTYPE, to indicate the
type of calendar user; MEMBER, to indicate the groups that the
attendee belongs to; DELEGATED-TO, to indicate the calendar users
that the original request was delegated to; and DELEGATED-FROM, to
indicate whom the request was delegated from; SENT-BY, to indicate
whom is acting on behalf of the ATTENDEE; and DIR, to indicate the
URI that points to the directory information corresponding to the
attendee. These property parameters can be specified on an "ATTENDEE"
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property in either a "VEVENT", "VTODO" or "VJOURNAL" calendar
component. They MUST not be specified in an "ATTENDEE" property in a
"VFREEBUSY" or "VALARM" calendar component. If the LANGUAGE property
parameter is specified, the identified language applies to the CN
parameter.
A recipient delegated a request MUST inherit the RSVP and ROLE values
from the attendee that delegated the request to them.
Multiple attendees can be specified by including multiple "ATTENDEE"
properties within the calendar component.
Format Definition: The property is defined by the following notation:
attendee = "ATTENDEE" attparam ":" cal-address CRLF
attparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" cutypeparam) / (";"memberparam) /
(";" roleparam) / (";" partstatparam) /
(";" rsvpparam) / (";" deltoparam) /
(";" delfromparam) / (";" sentbyparam) /
(";"cnparam) / (";" dirparam) /
(";" languageparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following are examples of this property's use for a to-
do:
ORGANIZER:MAILTO:jsmith@host1.com
ATTENDEE;MEMBER="MAILTO:DEV-GROUP@host2.com":
MAILTO:joecool@host2.com
ATTENDEE;DELEGATED-FROM="MAILTO:immud@host3.com":
MAILTO:ildoit@host1.com
The following is an example of this property used for specifying
multiple attendees to an event:
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ORGANIZER:MAILTO:jsmith@host1.com
ATTENDEE;ROLE=REQ-PARTICIPANT;PARTSTAT=TENTATIVE;CN=Henry Cabot
:MAILTO:hcabot@host2.com
ATTENDEE;ROLE=REQ-PARTICIPANT;DELEGATED-FROM="MAILTO:bob@host.com"
;PARTSTAT=ACCEPTED;CN=Jane Doe:MAILTO:jdoe@host1.com
The following is an example of this property with a URI to the
directory information associated with the attendee:
ATTENDEE;CN=John Smith;DIR="ldap://host.com:6666/o=eDABC%
20Industries,c=3DUS??(cn=3DBJim%20Dolittle)":MAILTO:jimdo@
host1.com
The following is an example of this property with "delegatee" and
"delegator" information for an event:
ORGANIZER;CN=John Smith:MAILTO:jsmith@host.com
ATTENDEE;ROLE=REQ-PARTICIPANT;PARTSTAT=TENTATIVE;DELEGATED-FROM=
"MAILTO:iamboss@host2.com";CN=Henry Cabot:MAILTO:hcabot@
host2.com
ATTENDEE;ROLE=NON-PARTICIPANT;PARTSTAT=DELEGATED;DELEGATED-TO=
"MAILTO:hcabot@host2.com";CN=The Big Cheese:MAILTO:iamboss
@host2.com
ATTENDEE;ROLE=REQ-PARTICIPANT;PARTSTAT=ACCEPTED;CN=Jane Doe
:MAILTO:jdoe@host1.com
Example: The following is an example of this property's use when
another calendar user is acting on behalf of the "Attendee":
ATTENDEE;SENT-BY=MAILTO:jan_doe@host1.com;CN=John Smith:MAILTO:
jsmith@host1.com
4.8.4.2 Contact
Property Name: CONTACT
Purpose: The property is used to represent contact information or
alternately a reference to contact information associated with the
calendar component.
Value Type: TEXT
Property Parameters: Non-standard, alternate text representation and
language property parameters can be specified on this property.
Conformance: The property can be specified in a "VEVENT", "VTODO",
"VJOURNAL" or "VFREEBUSY" calendar component.
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Description: The property value consists of textual contact
information. An alternative representation for the property value can
also be specified that refers to a URI pointing to an alternate form,
such as a vCard [RFC 2426], for the contact information.
Format Definition: The property is defined by the following notation:
contact = "CONTACT" contparam ":" text CRLF
contparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" altrepparam) / (";" languageparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following is an example of this property referencing
textual contact information:
CONTACT:Jim Dolittle\, ABC Industries\, +1-919-555-1234
The following is an example of this property with an alternate
representation of a LDAP URI to a directory entry containing the
contact information:
CONTACT;ALTREP="ldap://host.com:6666/o=3DABC%20Industries\,
c=3DUS??(cn=3DBJim%20Dolittle)":Jim Dolittle\, ABC Industries\,
+1-919-555-1234
The following is an example of this property with an alternate
representation of a MIME body part containing the contact
information, such as a vCard [RFC 2426] embedded in a [MIME-DIR]
content-type:
CONTACT;ALTREP="CID=<part3.msg970930T083000SILVER@host.com>":Jim
Dolittle\, ABC Industries\, +1-919-555-1234
The following is an example of this property referencing a network
resource, such as a vCard [RFC 2426] object containing the contact
information:
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CONTACT;ALTREP="http://host.com/pdi/jdoe.vcf":Jim
Dolittle\, ABC Industries\, +1-919-555-1234
4.8.4.3 Organizer
Property Name: ORGANIZER
Purpose: The property defines the organizer for a calendar component.
Value Type: CAL-ADDRESS
Property Parameters: Non-standard, language, common name, directory
entry reference, sent by property parameters can be specified on this
property.
Conformance: This property MUST be specified in an iCalendar object
that specifies a group scheduled calendar entity. This property MUST
be specified in an iCalendar object that specifies the publication of
a calendar user's busy time. This property MUST NOT be specified in
an iCalendar object that specifies only a time zone definition or
that defines calendar entities that are not group scheduled entities,
but are entities only on a single user's calendar.
Description: The property is specified within the "VEVENT", "VTODO",
"VJOURNAL calendar components to specify the organizer of a group
scheduled calendar entity. The property is specified within the
"VFREEBUSY" calendar component to specify the calendar user
requesting the free or busy time. When publishing a "VFREEBUSY"
calendar component, the property is used to specify the calendar that
the published busy time came from.
The property has the property parameters CN, for specifying the
common or display name associated with the "Organizer", DIR, for
specifying a pointer to the directory information associated with the
"Organizer", SENT-BY, for specifying another calendar user that is
acting on behalf of the "Organizer". The non-standard parameters may
also be specified on this property. If the LANGUAGE property
parameter is specified, the identified language applies to the CN
parameter value.
Format Definition: The property is defined by the following notation:
organizer = "ORGANIZER" orgparam ":"
cal-address CRLF
orgparam = *(
; the following are optional,
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; but MUST NOT occur more than once
(";" cnparam) / (";" dirparam) / (";" sentbyparam) /
(";" languageparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
Example: The following is an example of this property:
ORGANIZER;CN=John Smith:MAILTO:jsmith@host1.com
The following is an example of this property with a pointer to the
directory information associated with the organizer:
ORGANIZER;CN=JohnSmith;DIR="ldap://host.com:6666/o=3DDC%20Associ
ates,c=3DUS??(cn=3DJohn%20Smith)":MAILTO:jsmith@host1.com
The following is an example of this property used by another calendar
user who is acting on behalf of the organizer, with responses
intended to be sent back to the organizer, not the other calendar
user:
ORGANIZER;SENT-BY="MAILTO:jane_doe@host.com":
MAILTO:jsmith@host1.com
4.8.4.4 Recurrence ID
Property Name: RECURRENCE-ID
Purpose: This property is used in conjunction with the "UID" and
"SEQUENCE" property to identify a specific instance of a recurring
"VEVENT", "VTODO" or "VJOURNAL" calendar component. The property
value is the effective value of the "DTSTART" property of the
recurrence instance.
Value Type: The default value type for this property is DATE-TIME.
The time format can be any of the valid forms defined for a DATE-TIME
value type. See DATE-TIME value type definition for specific
interpretations of the various forms. The value type can be set to
DATE.
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Property Parameters: Non-standard property, value data type, time
zone identifier and recurrence identifier range parameters can be
specified on this property.
Conformance: This property can be specified in an iCalendar object
containing a recurring calendar component.
Description: The full range of calendar components specified by a
recurrence set is referenced by referring to just the "UID" property
value corresponding to the calendar component. The "RECURRENCE-ID"
property allows the reference to an individual instance within the
recurrence set.
If the value of the "DTSTART" property is a DATE type value, then the
value MUST be the calendar date for the recurrence instance.
The date/time value is set to the time when the original recurrence
instance would occur; meaning that if the intent is to change a
Friday meeting to Thursday, the date/time is still set to the
original Friday meeting.
The "RECURRENCE-ID" property is used in conjunction with the "UID"
and "SEQUENCE" property to identify a particular instance of a
recurring event, to-do or journal. For a given pair of "UID" and
"SEQUENCE" property values, the "RECURRENCE-ID" value for a
recurrence instance is fixed. When the definition of the recurrence
set for a calendar component changes, and hence the "SEQUENCE"
property value changes, the "RECURRENCE-ID" for a given recurrence
instance might also change.The "RANGE" parameter is used to specify
the effective range of recurrence instances from the instance
specified by the "RECURRENCE-ID" property value. The default value
for the range parameter is the single recurrence instance only. The
value can also be "THISANDPRIOR" to indicate a range defined by the
given recurrence instance and all prior instances or the value can be
"THISANDFUTURE" to indicate a range defined by the given recurrence
instance and all subsequent instances.
Format Definition: The property is defined by the following notation:
recurid = "RECURRENCE-ID" ridparam ":" ridval CRLF
ridparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" "VALUE" "=" ("DATE-TIME" / "DATE)) /
(";" tzidparam) / (";" rangeparam) /
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; the following is optional,
; and MAY occur more than once
(";" xparam)
)
ridval = date-time / date
;Value MUST match value type
Example: The following are examples of this property:
RECURRENCE-ID;VALUE=DATE:19960401
RECURRENCE-ID;RANGE=THISANDFUTURE:19960120T120000Z
4.8.4.5 Related To
Property Name: RELATED-TO
Purpose: The property is used to represent a relationship or
reference between one calendar component and another.
Value Type: TEXT
Property Parameters: Non-standard and relationship type property
parameters can be specified on this property.
Conformance: The property can be specified one or more times in the
"VEVENT", "VTODO" or "VJOURNAL" calendar components.
Description: The property value consists of the persistent, globally
unique identifier of another calendar component. This value would be
represented in a calendar component by the "UID" property.
By default, the property value points to another calendar component
that has a PARENT relationship to the referencing object. The
"RELTYPE" property parameter is used to either explicitly state the
default PARENT relationship type to the referenced calendar component
or to override the default PARENT relationship type and specify
either a CHILD or SIBLING relationship. The PARENT relationship
indicates that the calendar component is a subordinate of the
referenced calendar component. The CHILD relationship indicates that
the calendar component is a superior of the referenced calendar
component. The SIBLING relationship indicates that the calendar
component is a peer of the referenced calendar component.
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Changes to a calendar component referenced by this property can have
an implicit impact on the related calendar component. For example, if
a group event changes its start or end date or time, then the
related, dependent events will need to have their start and end dates
changed in a corresponding way. Similarly, if a PARENT calendar
component is canceled or deleted, then there is an implied impact to
the related CHILD calendar components. This property is intended only
to provide information on the relationship of calendar components. It
is up to the target calendar system to maintain any property
implications of this relationship.
Format Definition: The property is defined by the following notation:
related = "RELATED-TO" [relparam] ":" text CRLF
relparam = *(
; the following is optional,
; but MUST NOT occur more than once
(";" reltypeparam) /
; the following is optional,
; and MAY occur more than once
(";" xparm)
)
The following is an example of this property:
RELATED-TO:<jsmith.part7.19960817T083000.xyzMail@host3.com>
RELATED-TO:<19960401-080045-4000F192713-0052@host1.com>
4.8.4.6 Uniform Resource Locator
Property Name: URL
Purpose: This property defines a Uniform Resource Locator (URL)
associated with the iCalendar object.
Value Type: URI
Property Parameters: Non-standard property parameters can be
specified on this property.
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Conformance: This property can be specified once in the "VEVENT",
"VTODO", "VJOURNAL" or "VFREEBUSY" calendar components.
Description: This property may be used in a calendar component to
convey a location where a more dynamic rendition of the calendar
information associated with the calendar component can be found. This
memo does not attempt to standardize the form of the URI, nor the
format of the resource pointed to by the property value. If the URL
property and Content-Location MIME header are both specified, they
MUST point to the same resource.
Format Definition: The property is defined by the following notation:
url = "URL" urlparam ":" uri CRLF
urlparam = *(";" xparam)
Example: The following is an example of this property:
URL:http://abc.com/pub/calendars/jsmith/mytime.ics
4.8.4.7 Unique Identifier
Property Name: UID
Purpose: This property defines the persistent, globally unique
identifier for the calendar component.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property MUST be specified in the "VEVENT", "VTODO",
"VJOURNAL" or "VFREEBUSY" calendar components.
Description: The UID itself MUST be a globally unique identifier. The
generator of the identifier MUST guarantee that the identifier is
unique. There are several algorithms that can be used to accomplish
this. The identifier is RECOMMENDED to be the identical syntax to the
[RFC 822] addr-spec. A good method to assure uniqueness is to put the
domain name or a domain literal IP address of the host on which the
identifier was created on the right hand side of the "@", and on the
left hand side, put a combination of the current calendar date and
time of day (i.e., formatted in as a DATE-TIME value) along with some
other currently unique (perhaps sequential) identifier available on
the system (for example, a process id number). Using a date/time
value on the left hand side and a domain name or domain literal on
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the right hand side makes it possible to guarantee uniqueness since
no two hosts should be using the same domain name or IP address at
the same time. Though other algorithms will work, it is RECOMMENDED
that the right hand side contain some domain identifier (either of
the host itself or otherwise) such that the generator of the message
identifier can guarantee the uniqueness of the left hand side within
the scope of that domain.
This is the method for correlating scheduling messages with the
referenced "VEVENT", "VTODO", or "VJOURNAL" calendar component.
The full range of calendar components specified by a recurrence set
is referenced by referring to just the "UID" property value
corresponding to the calendar component. The "RECURRENCE-ID" property
allows the reference to an individual instance within the recurrence
set.
This property is an important method for group scheduling
applications to match requests with later replies, modifications or
deletion requests. Calendaring and scheduling applications MUST
generate this property in "VEVENT", "VTODO" and "VJOURNAL" calendar
components to assure interoperability with other group scheduling
applications. This identifier is created by the calendar system that
generates an iCalendar object.
Implementations MUST be able to receive and persist values of at
least 255 characters for this property.
Format Definition: The property is defined by the following notation:
uid = "UID" uidparam ":" text CRLF
uidparam = *(";" xparam)
Example: The following is an example of this property:
UID:19960401T080045Z-4000F192713-0052@host1.com
4.8.5 Recurrence Component Properties
The following properties specify recurrence information in calendar
components.
4.8.5.1 Exception Date/Times
Property Name: EXDATE
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Purpose: This property defines the list of date/time exceptions for a
recurring calendar component.
Value Type: The default value type for this property is DATE-TIME.
The value type can be set to DATE.
Property Parameters: Non-standard, value data type and time zone
identifier property parameters can be specified on this property.
Conformance: This property can be specified in an iCalendar object
that includes a recurring calendar component.
Description: The exception dates, if specified, are used in computing
the recurrence set. The recurrence set is the complete set of
recurrence instances for a calendar component. The recurrence set is
generated by considering the initial "DTSTART" property along with
the "RRULE", "RDATE", "EXDATE" and "EXRULE" properties contained
within the iCalendar object. The "DTSTART" property defines the first
instance in the recurrence set. Multiple instances of the "RRULE" and
"EXRULE" properties can also be specified to define more
sophisticated recurrence sets. The final recurrence set is generated
by gathering all of the start date-times generated by any of the
specified "RRULE" and "RDATE" properties, and then excluding any
start date and times which fall within the union of start date and
times generated by any specified "EXRULE" and "EXDATE" properties.
This implies that start date and times within exclusion related
properties (i.e., "EXDATE" and "EXRULE") take precedence over those
specified by inclusion properties (i.e., "RDATE" and "RRULE"). Where
duplicate instances are generated by the "RRULE" and "RDATE"
properties, only one recurrence is considered. Duplicate instances
are ignored.
The "EXDATE" property can be used to exclude the value specified in
"DTSTART". However, in such cases the original "DTSTART" date MUST
still be maintained by the calendaring and scheduling system because
the original "DTSTART" value has inherent usage dependencies by other
properties such as the "RECURRENCE-ID".
Format Definition: The property is defined by the following notation:
exdate = "EXDATE" exdtparam ":" exdtval *("," exdtval) CRLF
exdtparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
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(";" tzidparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
exdtval = date-time / date
;Value MUST match value type
Example: The following is an example of this property:
EXDATE:19960402T010000Z,19960403T010000Z,19960404T010000Z
4.8.5.2 Exception Rule
Property Name: EXRULE
Purpose: This property defines a rule or repeating pattern for an
exception to a recurrence set.
Value Type: RECUR
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified in "VEVENT", "VTODO" or
"VJOURNAL" calendar components.
Description: The exception rule, if specified, is used in computing
the recurrence set. The recurrence set is the complete set of
recurrence instances for a calendar component. The recurrence set is
generated by considering the initial "DTSTART" property along with
the "RRULE", "RDATE", "EXDATE" and "EXRULE" properties contained
within the iCalendar object. The "DTSTART" defines the first instance
in the recurrence set. Multiple instances of the "RRULE" and "EXRULE"
properties can also be specified to define more sophisticated
recurrence sets. The final recurrence set is generated by gathering
all of the start date-times generated by any of the specified "RRULE"
and "RDATE" properties, and excluding any start date and times which
fall within the union of start date and times generated by any
specified "EXRULE" and "EXDATE" properties. This implies that start
date and times within exclusion related properties (i.e., "EXDATE"
and "EXRULE") take precedence over those specified by inclusion
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properties (i.e., "RDATE" and "RRULE"). Where duplicate instances are
generated by the "RRULE" and "RDATE" properties, only one recurrence
is considered. Duplicate instances are ignored.
The "EXRULE" property can be used to exclude the value specified in
"DTSTART". However, in such cases the original "DTSTART" date MUST
still be maintained by the calendaring and scheduling system because
the original "DTSTART" value has inherent usage dependencies by other
properties such as the "RECURRENCE-ID".
Format Definition: The property is defined by the following notation:
exrule = "EXRULE" exrparam ":" recur CRLF
exrparam = *(";" xparam)
Example: The following are examples of this property. Except every
other week, on Tuesday and Thursday for 4 occurrences:
EXRULE:FREQ=WEEKLY;COUNT=4;INTERVAL=2;BYDAY=TU,TH
Except daily for 10 occurrences:
EXRULE:FREQ=DAILY;COUNT=10
Except yearly in June and July for 8 occurrences:
EXRULE:FREQ=YEARLY;COUNT=8;BYMONTH=6,7
4.8.5.3 Recurrence Date/Times
Property Name: RDATE
Purpose: This property defines the list of date/times for a
recurrence set.
Value Type: The default value type for this property is DATE-TIME.
The value type can be set to DATE or PERIOD.
Property Parameters: Non-standard, value data type and time zone
identifier property parameters can be specified on this property.
Conformance: The property can be specified in "VEVENT", "VTODO",
"VJOURNAL" or "VTIMEZONE" calendar components.
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Description: This property can appear along with the "RRULE" property
to define an aggregate set of repeating occurrences. When they both
appear in an iCalendar object, the recurring events are defined by
the union of occurrences defined by both the "RDATE" and "RRULE".
The recurrence dates, if specified, are used in computing the
recurrence set. The recurrence set is the complete set of recurrence
instances for a calendar component. The recurrence set is generated
by considering the initial "DTSTART" property along with the "RRULE",
"RDATE", "EXDATE" and "EXRULE" properties contained within the
iCalendar object. The "DTSTART" property defines the first instance
in the recurrence set. Multiple instances of the "RRULE" and "EXRULE"
properties can also be specified to define more sophisticated
recurrence sets. The final recurrence set is generated by gathering
all of the start date/times generated by any of the specified "RRULE"
and "RDATE" properties, and excluding any start date/times which fall
within the union of start date/times generated by any specified
"EXRULE" and "EXDATE" properties. This implies that start date/times
within exclusion related properties (i.e., "EXDATE" and "EXRULE")
take precedence over those specified by inclusion properties (i.e.,
"RDATE" and "RRULE"). Where duplicate instances are generated by the
"RRULE" and "RDATE" properties, only one recurrence is considered.
Duplicate instances are ignored.
Format Definition: The property is defined by the following notation:
rdate = "RDATE" rdtparam ":" rdtval *("," rdtval) CRLF
rdtparam = *(
; the following are optional,
; but MUST NOT occur more than once
(";" "VALUE" "=" ("DATE-TIME" / "DATE" / "PERIOD")) /
(";" tzidparam) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
rdtval = date-time / date / period
;Value MUST match value type
Example: The following are examples of this property:
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RDATE:19970714T123000Z
RDATE;TZID=US-EASTERN:19970714T083000
RDATE;VALUE=PERIOD:19960403T020000Z/19960403T040000Z,
19960404T010000Z/PT3H
RDATE;VALUE=DATE:19970101,19970120,19970217,19970421
19970526,19970704,19970901,19971014,19971128,19971129,19971225
4.8.5.4 Recurrence Rule
Property Name: RRULE
Purpose: This property defines a rule or repeating pattern for
recurring events, to-dos, or time zone definitions.
Value Type: RECUR
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified one or more times in
recurring "VEVENT", "VTODO" and "VJOURNAL" calendar components. It
can also be specified once in each STANDARD or DAYLIGHT sub-component
of the "VTIMEZONE" calendar component.
Description: The recurrence rule, if specified, is used in computing
the recurrence set. The recurrence set is the complete set of
recurrence instances for a calendar component. The recurrence set is
generated by considering the initial "DTSTART" property along with
the "RRULE", "RDATE", "EXDATE" and "EXRULE" properties contained
within the iCalendar object. The "DTSTART" property defines the first
instance in the recurrence set. Multiple instances of the "RRULE" and
"EXRULE" properties can also be specified to define more
sophisticated recurrence sets. The final recurrence set is generated
by gathering all of the start date/times generated by any of the
specified "RRULE" and "RDATE" properties, and excluding any start
date/times which fall within the union of start date/times generated
by any specified "EXRULE" and "EXDATE" properties. This implies that
start date/times within exclusion related properties (i.e., "EXDATE"
and "EXRULE") take precedence over those specified by inclusion
properties (i.e., "RDATE" and "RRULE"). Where duplicate instances are
generated by the "RRULE" and "RDATE" properties, only one recurrence
is considered. Duplicate instances are ignored.
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The "DTSTART" and "DTEND" property pair or "DTSTART" and "DURATION"
property pair, specified within the iCalendar object defines the
first instance of the recurrence. When used with a recurrence rule,
the "DTSTART" and "DTEND" properties MUST be specified in local time
and the appropriate set of "VTIMEZONE" calendar components MUST be
included. For detail on the usage of the "VTIMEZONE" calendar
component, see the "VTIMEZONE" calendar component definition.
Any duration associated with the iCalendar object applies to all
members of the generated recurrence set. Any modified duration for
specific recurrences MUST be explicitly specified using the "RDATE"
property.
Format Definition: This property is defined by the following
notation:
rrule = "RRULE" rrulparam ":" recur CRLF
rrulparam = *(";" xparam)
Example: All examples assume the Eastern United States time zone.
Daily for 10 occurrences:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=DAILY;COUNT=10
==> (1997 9:00 AM EDT)September 2-11
Daily until December 24, 1997:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=DAILY;UNTIL=19971224T000000Z
==> (1997 9:00 AM EDT)September 2-30;October 1-25
(1997 9:00 AM EST)October 26-31;November 1-30;December 1-23
Every other day - forever:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=DAILY;INTERVAL=2
==> (1997 9:00 AM EDT)September2,4,6,8...24,26,28,30;
October 2,4,6...20,22,24
(1997 9:00 AM EST)October 26,28,30;November 1,3,5,7...25,27,29;
Dec 1,3,...
Every 10 days, 5 occurrences:
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RFC 2445 iCalendar November 1998
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=DAILY;INTERVAL=10;COUNT=5
==> (1997 9:00 AM EDT)September 2,12,22;October 2,12
Everyday in January, for 3 years:
DTSTART;TZID=US-Eastern:19980101T090000
RRULE:FREQ=YEARLY;UNTIL=20000131T090000Z;
BYMONTH=1;BYDAY=SU,MO,TU,WE,TH,FR,SA
or
RRULE:FREQ=DAILY;UNTIL=20000131T090000Z;BYMONTH=1
==> (1998 9:00 AM EDT)January 1-31
(1999 9:00 AM EDT)January 1-31
(2000 9:00 AM EDT)January 1-31
Weekly for 10 occurrences
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=WEEKLY;COUNT=10
==> (1997 9:00 AM EDT)September 2,9,16,23,30;October 7,14,21
(1997 9:00 AM EST)October 28;November 4
Weekly until December 24, 1997
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=WEEKLY;UNTIL=19971224T000000Z
==> (1997 9:00 AM EDT)September 2,9,16,23,30;October 7,14,21
(1997 9:00 AM EST)October 28;November 4,11,18,25;
December 2,9,16,23
Every other week - forever:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=WEEKLY;INTERVAL=2;WKST=SU
==> (1997 9:00 AM EDT)September 2,16,30;October 14
(1997 9:00 AM EST)October 28;November 11,25;December 9,23
(1998 9:00 AM EST)January 6,20;February
...
Weekly on Tuesday and Thursday for 5 weeks:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=WEEKLY;UNTIL=19971007T000000Z;WKST=SU;BYDAY=TU,TH
or
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RFC 2445 iCalendar November 1998
RRULE:FREQ=WEEKLY;COUNT=10;WKST=SU;BYDAY=TU,TH
==> (1997 9:00 AM EDT)September 2,4,9,11,16,18,23,25,30;October 2
Every other week on Monday, Wednesday and Friday until December 24,
1997, but starting on Tuesday, September 2, 1997:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=WEEKLY;INTERVAL=2;UNTIL=19971224T000000Z;WKST=SU;
BYDAY=MO,WE,FR
==> (1997 9:00 AM EDT)September 2,3,5,15,17,19,29;October
1,3,13,15,17
(1997 9:00 AM EST)October 27,29,31;November 10,12,14,24,26,28;
December 8,10,12,22
Every other week on Tuesday and Thursday, for 8 occurrences:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=8;WKST=SU;BYDAY=TU,TH
==> (1997 9:00 AM EDT)September 2,4,16,18,30;October 2,14,16
Monthly on the 1st Friday for ten occurrences:
DTSTART;TZID=US-Eastern:19970905T090000
RRULE:FREQ=MONTHLY;COUNT=10;BYDAY=1FR
==> (1997 9:00 AM EDT)September 5;October 3
(1997 9:00 AM EST)November 7;Dec 5
(1998 9:00 AM EST)January 2;February 6;March 6;April 3
(1998 9:00 AM EDT)May 1;June 5
Monthly on the 1st Friday until December 24, 1997:
DTSTART;TZID=US-Eastern:19970905T090000
RRULE:FREQ=MONTHLY;UNTIL=19971224T000000Z;BYDAY=1FR
==> (1997 9:00 AM EDT)September 5;October 3
(1997 9:00 AM EST)November 7;December 5
Every other month on the 1st and last Sunday of the month for 10
occurrences:
DTSTART;TZID=US-Eastern:19970907T090000
RRULE:FREQ=MONTHLY;INTERVAL=2;COUNT=10;BYDAY=1SU,-1SU
==> (1997 9:00 AM EDT)September 7,28
(1997 9:00 AM EST)November 2,30
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(1998 9:00 AM EST)January 4,25;March 1,29
(1998 9:00 AM EDT)May 3,31
Monthly on the second to last Monday of the month for 6 months:
DTSTART;TZID=US-Eastern:19970922T090000
RRULE:FREQ=MONTHLY;COUNT=6;BYDAY=-2MO
==> (1997 9:00 AM EDT)September 22;October 20
(1997 9:00 AM EST)November 17;December 22
(1998 9:00 AM EST)January 19;February 16
Monthly on the third to the last day of the month, forever:
DTSTART;TZID=US-Eastern:19970928T090000
RRULE:FREQ=MONTHLY;BYMONTHDAY=-3
==> (1997 9:00 AM EDT)September 28
(1997 9:00 AM EST)October 29;November 28;December 29
(1998 9:00 AM EST)January 29;February 26
...
Monthly on the 2nd and 15th of the month for 10 occurrences:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=MONTHLY;COUNT=10;BYMONTHDAY=2,15
==> (1997 9:00 AM EDT)September 2,15;October 2,15
(1997 9:00 AM EST)November 2,15;December 2,15
(1998 9:00 AM EST)January 2,15
Monthly on the first and last day of the month for 10 occurrences:
DTSTART;TZID=US-Eastern:19970930T090000
RRULE:FREQ=MONTHLY;COUNT=10;BYMONTHDAY=1,-1
==> (1997 9:00 AM EDT)September 30;October 1
(1997 9:00 AM EST)October 31;November 1,30;December 1,31
(1998 9:00 AM EST)January 1,31;February 1
Every 18 months on the 10th thru 15th of the month for 10
occurrences:
DTSTART;TZID=US-Eastern:19970910T090000
RRULE:FREQ=MONTHLY;INTERVAL=18;COUNT=10;BYMONTHDAY=10,11,12,13,14,
15
==> (1997 9:00 AM EDT)September 10,11,12,13,14,15
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RFC 2445 iCalendar November 1998
(1999 9:00 AM EST)March 10,11,12,13
Every Tuesday, every other month:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=MONTHLY;INTERVAL=2;BYDAY=TU
==> (1997 9:00 AM EDT)September 2,9,16,23,30
(1997 9:00 AM EST)November 4,11,18,25
(1998 9:00 AM EST)January 6,13,20,27;March 3,10,17,24,31
...
Yearly in June and July for 10 occurrences:
DTSTART;TZID=US-Eastern:19970610T090000
RRULE:FREQ=YEARLY;COUNT=10;BYMONTH=6,7
==> (1997 9:00 AM EDT)June 10;July 10
(1998 9:00 AM EDT)June 10;July 10
(1999 9:00 AM EDT)June 10;July 10
(2000 9:00 AM EDT)June 10;July 10
(2001 9:00 AM EDT)June 10;July 10
Note: Since none of the BYDAY, BYMONTHDAY or BYYEARDAY components
are specified, the day is gotten from DTSTART
Every other year on January, February, and March for 10 occurrences:
DTSTART;TZID=US-Eastern:19970310T090000
RRULE:FREQ=YEARLY;INTERVAL=2;COUNT=10;BYMONTH=1,2,3
==> (1997 9:00 AM EST)March 10
(1999 9:00 AM EST)January 10;February 10;March 10
(2001 9:00 AM EST)January 10;February 10;March 10
(2003 9:00 AM EST)January 10;February 10;March 10
Every 3rd year on the 1st, 100th and 200th day for 10 occurrences:
DTSTART;TZID=US-Eastern:19970101T090000
RRULE:FREQ=YEARLY;INTERVAL=3;COUNT=10;BYYEARDAY=1,100,200
==> (1997 9:00 AM EST)January 1
(1997 9:00 AM EDT)April 10;July 19
(2000 9:00 AM EST)January 1
(2000 9:00 AM EDT)April 9;July 18
(2003 9:00 AM EST)January 1
(2003 9:00 AM EDT)April 10;July 19
(2006 9:00 AM EST)January 1
Every 20th Monday of the year, forever:
Dawson & Stenerson Standards Track [Page 122]
RFC 2445 iCalendar November 1998
DTSTART;TZID=US-Eastern:19970519T090000
RRULE:FREQ=YEARLY;BYDAY=20MO
==> (1997 9:00 AM EDT)May 19
(1998 9:00 AM EDT)May 18
(1999 9:00 AM EDT)May 17
...
Monday of week number 20 (where the default start of the week is
Monday), forever:
DTSTART;TZID=US-Eastern:19970512T090000
RRULE:FREQ=YEARLY;BYWEEKNO=20;BYDAY=MO
==> (1997 9:00 AM EDT)May 12
(1998 9:00 AM EDT)May 11
(1999 9:00 AM EDT)May 17
...
Every Thursday in March, forever:
DTSTART;TZID=US-Eastern:19970313T090000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=TH
==> (1997 9:00 AM EST)March 13,20,27
(1998 9:00 AM EST)March 5,12,19,26
(1999 9:00 AM EST)March 4,11,18,25
...
Every Thursday, but only during June, July, and August, forever:
DTSTART;TZID=US-Eastern:19970605T090000
RRULE:FREQ=YEARLY;BYDAY=TH;BYMONTH=6,7,8
==> (1997 9:00 AM EDT)June 5,12,19,26;July 3,10,17,24,31;
August 7,14,21,28
(1998 9:00 AM EDT)June 4,11,18,25;July 2,9,16,23,30;
August 6,13,20,27
(1999 9:00 AM EDT)June 3,10,17,24;July 1,8,15,22,29;
August 5,12,19,26
...
Every Friday the 13th, forever:
DTSTART;TZID=US-Eastern:19970902T090000
EXDATE;TZID=US-Eastern:19970902T090000
RRULE:FREQ=MONTHLY;BYDAY=FR;BYMONTHDAY=13
Dawson & Stenerson Standards Track [Page 123]
RFC 2445 iCalendar November 1998
==> (1998 9:00 AM EST)February 13;March 13;November 13
(1999 9:00 AM EDT)August 13
(2000 9:00 AM EDT)October 13
...
The first Saturday that follows the first Sunday of the month,
forever:
DTSTART;TZID=US-Eastern:19970913T090000
RRULE:FREQ=MONTHLY;BYDAY=SA;BYMONTHDAY=7,8,9,10,11,12,13
==> (1997 9:00 AM EDT)September 13;October 11
(1997 9:00 AM EST)November 8;December 13
(1998 9:00 AM EST)January 10;February 7;March 7
(1998 9:00 AM EDT)April 11;May 9;June 13...
...
Every four years, the first Tuesday after a Monday in November,
forever (U.S. Presidential Election day):
DTSTART;TZID=US-Eastern:19961105T090000
RRULE:FREQ=YEARLY;INTERVAL=4;BYMONTH=11;BYDAY=TU;BYMONTHDAY=2,3,4,
5,6,7,8
==> (1996 9:00 AM EST)November 5
(2000 9:00 AM EST)November 7
(2004 9:00 AM EST)November 2
...
The 3rd instance into the month of one of Tuesday, Wednesday or
Thursday, for the next 3 months:
DTSTART;TZID=US-Eastern:19970904T090000
RRULE:FREQ=MONTHLY;COUNT=3;BYDAY=TU,WE,TH;BYSETPOS=3
==> (1997 9:00 AM EDT)September 4;October 7
(1997 9:00 AM EST)November 6
The 2nd to last weekday of the month:
DTSTART;TZID=US-Eastern:19970929T090000
RRULE:FREQ=MONTHLY;BYDAY=MO,TU,WE,TH,FR;BYSETPOS=-2
==> (1997 9:00 AM EDT)September 29
(1997 9:00 AM EST)October 30;November 27;December 30
(1998 9:00 AM EST)January 29;February 26;March 30
...
Dawson & Stenerson Standards Track [Page 124]
RFC 2445 iCalendar November 1998
Every 3 hours from 9:00 AM to 5:00 PM on a specific day:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=HOURLY;INTERVAL=3;UNTIL=19970902T170000Z
==> (September 2, 1997 EDT)09:00,12:00,15:00
Every 15 minutes for 6 occurrences:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=MINUTELY;INTERVAL=15;COUNT=6
==> (September 2, 1997 EDT)09:00,09:15,09:30,09:45,10:00,10:15
Every hour and a half for 4 occurrences:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=MINUTELY;INTERVAL=90;COUNT=4
==> (September 2, 1997 EDT)09:00,10:30;12:00;13:30
Every 20 minutes from 9:00 AM to 4:40 PM every day:
DTSTART;TZID=US-Eastern:19970902T090000
RRULE:FREQ=DAILY;BYHOUR=9,10,11,12,13,14,15,16;BYMINUTE=0,20,40
or
RRULE:FREQ=MINUTELY;INTERVAL=20;BYHOUR=9,10,11,12,13,14,15,16
==> (September 2, 1997 EDT)9:00,9:20,9:40,10:00,10:20,
... 16:00,16:20,16:40
(September 3, 1997 EDT)9:00,9:20,9:40,10:00,10:20,
...16:00,16:20,16:40
...
An example where the days generated makes a difference because of
WKST:
DTSTART;TZID=US-Eastern:19970805T090000
RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=4;BYDAY=TU,SU;WKST=MO
==> (1997 EDT)Aug 5,10,19,24
changing only WKST from MO to SU, yields different results...
DTSTART;TZID=US-Eastern:19970805T090000
RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=4;BYDAY=TU,SU;WKST=SU
==> (1997 EDT)August 5,17,19,31
Dawson & Stenerson Standards Track [Page 125]
RFC 2445 iCalendar November 1998
4.8.6 Alarm Component Properties
The following properties specify alarm information in calendar
components.
4.8.6.1 Action
Property Name: ACTION
Purpose: This property defines the action to be invoked when an alarm
is triggered.
Value Type: TEXT
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property MUST be specified once in a "VALARM"
calendar component.
Description: Each "VALARM" calendar component has a particular type
of action associated with it. This property specifies the type of
action
Format Definition: The property is defined by the following notation:
action = "ACTION" actionparam ":" actionvalue CRLF
actionparam = *(";" xparam)
actionvalue = "AUDIO" / "DISPLAY" / "EMAIL" / "PROCEDURE"
/ iana-token / x-name
Example: The following are examples of this property in a "VALARM"
calendar component:
ACTION:AUDIO
ACTION:DISPLAY
ACTION:PROCEDURE
4.8.6.2 Repeat Count
Property Name: REPEAT
Purpose: This property defines the number of time the alarm should be
repeated, after the initial trigger.
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RFC 2445 iCalendar November 1998
Value Type: INTEGER
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified in a "VALARM" calendar
component.
Description: If the alarm triggers more than once, then this property
MUST be specified along with the "DURATION" property.
Format Definition: The property is defined by the following notation:
repeatcnt = "REPEAT" repparam ":" integer CRLF
;Default is "0", zero.
repparam = *(";" xparam)
Example: The following is an example of this property for an alarm
that repeats 4 additional times with a 5 minute delay after the
initial triggering of the alarm:
REPEAT:4
DURATION:PT5M
4.8.6.3 Trigger
Property Name: TRIGGER
Purpose: This property specifies when an alarm will trigger.
Value Type: The default value type is DURATION. The value type can be
set to a DATE-TIME value type, in which case the value MUST specify a
UTC formatted DATE-TIME value.
Property Parameters: Non-standard, value data type, time zone
identifier or trigger relationship property parameters can be
specified on this property. The trigger relationship property
parameter MUST only be specified when the value type is DURATION.
Conformance: This property MUST be specified in the "VALARM" calendar
component.
Description: Within the "VALARM" calendar component, this property
defines when the alarm will trigger. The default value type is
DURATION, specifying a relative time for the trigger of the alarm.
The default duration is relative to the start of an event or to-do
that the alarm is associated with. The duration can be explicitly set
Dawson & Stenerson Standards Track [Page 127]
RFC 2445 iCalendar November 1998
to trigger from either the end or the start of the associated event
or to-do with the "RELATED" parameter. A value of START will set the
alarm to trigger off the start of the associated event or to-do. A
value of END will set the alarm to trigger off the end of the
associated event or to-do.
Either a positive or negative duration may be specified for the
"TRIGGER" property. An alarm with a positive duration is triggered
after the associated start or end of the event or to-do. An alarm
with a negative duration is triggered before the associated start or
end of the event or to-do.
The "RELATED" property parameter is not valid if the value type of
the property is set to DATE-TIME (i.e., for an absolute date and time
alarm trigger). If a value type of DATE-TIME is specified, then the
property value MUST be specified in the UTC time format. If an
absolute trigger is specified on an alarm for a recurring event or
to-do, then the alarm will only trigger for the specified absolute
date/time, along with any specified repeating instances.
If the trigger is set relative to START, then the "DTSTART" property
MUST be present in the associated "VEVENT" or "VTODO" calendar
component. If an alarm is specified for an event with the trigger set
relative to the END, then the "DTEND" property or the "DSTART" and
"DURATION' properties MUST be present in the associated "VEVENT"
calendar component. If the alarm is specified for a to-do with a
trigger set relative to the END, then either the "DUE" property or
the "DSTART" and "DURATION' properties MUST be present in the
associated "VTODO" calendar component.
Alarms specified in an event or to-do which is defined in terms of a
DATE value type will be triggered relative to 00:00:00 UTC on the
specified date. For example, if "DTSTART:19980205, then the duration
trigger will be relative to19980205T000000Z.
Format Definition: The property is defined by the following notation:
trigger = "TRIGGER" (trigrel / trigabs)
trigrel = *(
; the following are optional,
; but MUST NOT occur more than once
(";" "VALUE" "=" "DURATION") /
(";" trigrelparam) /
; the following is optional,
Dawson & Stenerson Standards Track [Page 128]
RFC 2445 iCalendar November 1998
; and MAY occur more than once
(";" xparam)
) ":" dur-value
trigabs = 1*(
; the following is REQUIRED,
; but MUST NOT occur more than once
(";" "VALUE" "=" "DATE-TIME") /
; the following is optional,
; and MAY occur more than once
(";" xparam)
) ":" date-time
Example: A trigger set 15 minutes prior to the start of the event or
to-do.
TRIGGER:-P15M
A trigger set 5 minutes after the end of the event or to-do.
TRIGGER;RELATED=END:P5M
A trigger set to an absolute date/time.
TRIGGER;VALUE=DATE-TIME:19980101T050000Z
4.8.7 Change Management Component Properties
The following properties specify change management information in
calendar components.
4.8.7.1 Date/Time Created
Property Name: CREATED
Purpose: This property specifies the date and time that the calendar
information was created by the calendar user agent in the calendar
store.
Note: This is analogous to the creation date and time for a file
in the file system.
Dawson & Stenerson Standards Track [Page 129]
RFC 2445 iCalendar November 1998
Value Type: DATE-TIME
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property can be specified once in "VEVENT", "VTODO"
or "VJOURNAL" calendar components.
Description: The date and time is a UTC value.
Format Definition: The property is defined by the following notation:
created = "CREATED" creaparam ":" date-time CRLF
creaparam = *(";" xparam)
Example: The following is an example of this property:
CREATED:19960329T133000Z
4.8.7.2 Date/Time Stamp
Property Name: DTSTAMP
Purpose: The property indicates the date/time that the instance of
the iCalendar object was created.
Value Type: DATE-TIME
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property MUST be included in the "VEVENT", "VTODO",
"VJOURNAL" or "VFREEBUSY" calendar components.
Description: The value MUST be specified in the UTC time format.
This property is also useful to protocols such as [IMIP] that have
inherent latency issues with the delivery of content. This property
will assist in the proper sequencing of messages containing iCalendar
objects.
This property is different than the "CREATED" and "LAST-MODIFIED"
properties. These two properties are used to specify when the
particular calendar data in the calendar store was created and last
modified. This is different than when the iCalendar object
representation of the calendar service information was created or
last modified.
Dawson & Stenerson Standards Track [Page 130]
RFC 2445 iCalendar November 1998
Format Definition: The property is defined by the following notation:
dtstamp = "DTSTAMP" stmparam ":" date-time CRLF
stmparam = *(";" xparam)
Example:
DTSTAMP:19971210T080000Z
4.8.7.3 Last Modified
Property Name: LAST-MODIFIED
Purpose: The property specifies the date and time that the
information associated with the calendar component was last revised
in the calendar store.
Note: This is analogous to the modification date and time for a
file in the file system.
Value Type: DATE-TIME
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: This property can be specified in the "EVENT", "VTODO",
"VJOURNAL" or "VTIMEZONE" calendar components.
Description: The property value MUST be specified in the UTC time
format.
Format Definition: The property is defined by the following notation:
last-mod = "LAST-MODIFIED" lstparam ":" date-time CRLF
lstparam = *(";" xparam)
Example: The following is are examples of this property:
LAST-MODIFIED:19960817T133000Z
4.8.7.4 Sequence Number
Property Name: SEQUENCE
Purpose: This property defines the revision sequence number of the
calendar component within a sequence of revisions.
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RFC 2445 iCalendar November 1998
Value Type: integer
Property Parameters: Non-standard property parameters can be
specified on this property.
Conformance: The property can be specified in "VEVENT", "VTODO" or
"VJOURNAL" calendar component.
Description: When a calendar component is created, its sequence
number is zero (US-ASCII decimal 48). It is monotonically incremented
by the "Organizer's" CUA each time the "Organizer" makes a
significant revision to the calendar component. When the "Organizer"
makes changes to one of the following properties, the sequence number
MUST be incremented:
. "DTSTART"
. "DTEND"
. "DUE"
. "RDATE"
. "RRULE"
. "EXDATE"
. "EXRULE"
. "STATUS"
In addition, changes made by the "Organizer" to other properties can
also force the sequence number to be incremented. The "Organizer" CUA
MUST increment the sequence number when ever it makes changes to
properties in the calendar component that the "Organizer" deems will
jeopardize the validity of the participation status of the
"Attendees". For example, changing the location of a meeting from one
locale to another distant locale could effectively impact the
participation status of the "Attendees".
The "Organizer" includes this property in an iCalendar object that it
sends to an "Attendee" to specify the current version of the calendar
component.
The "Attendee" includes this property in an iCalendar object that it
sends to the "Organizer" to specify the version of the calendar
component that the "Attendee" is referring to.
Dawson & Stenerson Standards Track [Page 132]
RFC 2445 iCalendar November 1998
A change to the sequence number is not the mechanism that an
"Organizer" uses to request a response from the "Attendees". The
"RSVP" parameter on the "ATTENDEE" property is used by the
"Organizer" to indicate that a response from the "Attendees" is
requested.
Format Definition: This property is defined by the following
notation:
seq = "SEQUENCE" seqparam ":" integer CRLF
; Default is "0"
seqparam = *(";" xparam)
Example: The following is an example of this property for a calendar
component that was just created by the "Organizer".
SEQUENCE:0
The following is an example of this property for a calendar component
that has been revised two different times by the "Organizer".
SEQUENCE:2
4.8.8 Miscellaneous Component Properties
The following properties specify information about a number of
miscellaneous features of calendar components.
4.8.8.1 Non-standard Properties
Property Name: Any property name with a "X-" prefix
Purpose: This class of property provides a framework for defining
non-standard properties.
Value Type: TEXT
Property Parameters: Non-standard and language property parameters
can be specified on this property.
Conformance: This property can be specified in any calendar
component.
Description: The MIME Calendaring and Scheduling Content Type
provides a "standard mechanism for doing non-standard things". This
extension support is provided for implementers to "push the envelope"
on the existing version of the memo. Extension properties are
Dawson & Stenerson Standards Track [Page 133]
RFC 2445 iCalendar November 1998
specified by property and/or property parameter names that have the
prefix text of "X-" (the two character sequence: LATIN CAPITAL LETTER
X character followed by the HYPEN-MINUS character). It is recommended
that vendors concatenate onto this sentinel another short prefix text
to identify the vendor. This will facilitate readability of the
extensions and minimize possible collision of names between different
vendors. User agents that support this content type are expected to
be able to parse the extension properties and property parameters but
can ignore them.
At present, there is no registration authority for names of extension
properties and property parameters. The data type for this property
is TEXT. Optionally, the data type can be any of the other valid data
types.
Format Definition: The property is defined by the following notation:
x-prop = x-name *(";" xparam) [";" languageparam] ":" text CRLF
; Lines longer than 75 octets should be folded
Example: The following might be the ABC vendor's extension for an
audio-clip form of subject property:
X-ABC-MMSUBJ;X-ABC-MMSUBJTYPE=wave:http://load.noise.org/mysubj.wav
4.8.8.2 Request Status
Property Name: REQUEST-STATUS
Purpose: This property defines the status code returned for a
scheduling request.
Value Type: TEXT
Property Parameters: Non-standard and language property parameters
can be specified on this property.
Conformance: The property can be specified in "VEVENT", "VTODO",
"VJOURNAL" or "VFREEBUSY" calendar component.
Description: This property is used to return status code information
related to the processing of an associated iCalendar object. The data
type for this property is TEXT.
The value consists of a short return status component, a longer
return status description component, and optionally a status-specific
data component. The components of the value are separated by the
SEMICOLON character (US-ASCII decimal 59).
Dawson & Stenerson Standards Track [Page 134]
RFC 2445 iCalendar November 1998
The short return status is a PERIOD character (US-ASCII decimal 46)
separated 3-tuple of integers. For example, "3.1.1". The successive
levels of integers provide for a successive level of status code
granularity.
The following are initial classes for the return status code.
Individual iCalendar object methods will define specific return
status codes for these classes. In addition, other classes for the
return status code may be defined using the registration process
defined later in this memo.
|==============+===============================================|
| Short Return | Longer Return Status Description |
| Status Code | |
|==============+===============================================|
| 1.xx | Preliminary success. This class of status |
| | of status code indicates that the request has |
| | request has been initially processed but that |
| | completion is pending. |
|==============+===============================================|
| 2.xx | Successful. This class of status code |
| | indicates that the request was completed |
| | successfuly. However, the exact status code |
| | can indicate that a fallback has been taken. |
|==============+===============================================|
| 3.xx | Client Error. This class of status code |
| | indicates that the request was not successful.|
| | The error is the result of either a syntax or |
| | a semantic error in the client formatted |
| | request. Request should not be retried until |
| | the condition in the request is corrected. |
|==============+===============================================|
| 4.xx | Scheduling Error. This class of status code |
| | indicates that the request was not successful.|
| | Some sort of error occurred within the |
| | calendaring and scheduling service, not |
| | directly related to the request itself. |
|==============+===============================================|
Format Definition: The property is defined by the following notation:
rstatus = "REQUEST-STATUS" rstatparam ":"
statcode ";" statdesc [";" extdata]
rstatparam = *(
; the following is optional,
; but MUST NOT occur more than once
Dawson & Stenerson Standards Track [Page 135]
RFC 2445 iCalendar November 1998
(";" languageparm) /
; the following is optional,
; and MAY occur more than once
(";" xparam)
)
statcode = 1*DIGIT *("." 1*DIGIT)
;Hierarchical, numeric return status code
statdesc = text
;Textual status description
extdata = text
;Textual exception data. For example, the offending property
;name and value or complete property line.
Example: The following are some possible examples of this property.
The COMMA and SEMICOLON separator characters in the property value
are BACKSLASH character escaped because they appear in a text value.
REQUEST-STATUS:2.0;Success
REQUEST-STATUS:3.1;Invalid property value;DTSTART:96-Apr-01
REQUEST-STATUS:2.8; Success\, repeating event ignored. Scheduled
as a single event.;RRULE:FREQ=WEEKLY\;INTERVAL=2
REQUEST-STATUS:4.1;Event conflict. Date/time is busy.
REQUEST-STATUS:3.7;Invalid calendar user;ATTENDEE:
MAILTO:jsmith@host.com
5 iCalendar Object Examples
The following examples are provided as an informational source of
illustrative iCalendar objects consistent with this content type.
The following example specifies a three-day conference that begins at
8:00 AM EDT, September 18, 1996 and end at 6:00 PM EDT, September 20,
1996.
BEGIN:VCALENDAR PRODID:-//xyz Corp//NONSGML PDA Calendar Verson
1.0//EN VERSION:2.0 BEGIN:VEVENT DTSTAMP:19960704T120000Z
UID:uid1@host.com ORGANIZER:MAILTO:jsmith@host.com
DTSTART:19960918T143000Z DTEND:19960920T220000Z STATUS:CONFIRMED
Dawson & Stenerson Standards Track [Page 136]
RFC 2445 iCalendar November 1998
CATEGORIES:CONFERENCE SUMMARY:Networld+Interop Conference
DESCRIPTION:Networld+Interop Conference
and Exhibit\nAtlanta World Congress Center\n
Atlanta, Georgia END:VEVENT END:VCALENDAR
The following example specifies a group scheduled meeting that begin
at 8:30 AM EST on March 12, 1998 and end at 9:30 AM EST on March 12,
1998. The "Organizer" has scheduled the meeting with one or more
calendar users in a group. A time zone specification for Eastern
United States has been specified.
BEGIN:VCALENDAR
PRODID:-//RDU Software//NONSGML HandCal//EN
VERSION:2.0
BEGIN:VTIMEZONE
TZID:US-Eastern
BEGIN:STANDARD
DTSTART:19981025T020000
RDATE:19981025T020000
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:19990404T020000
RDATE:19990404T020000
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
END:DAYLIGHT
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:19980309T231000Z
UID:guid-1.host1.com
ORGANIZER;ROLE=CHAIR:MAILTO:mrbig@host.com
ATTENDEE;RSVP=TRUE;ROLE=REQ-PARTICIPANT;CUTYPE=GROUP:
MAILTO:employee-A@host.com
DESCRIPTION:Project XYZ Review Meeting
CATEGORIES:MEETING
CLASS:PUBLIC
CREATED:19980309T130000Z
SUMMARY:XYZ Project Review
DTSTART;TZID=US-Eastern:19980312T083000
DTEND;TZID=US-Eastern:19980312T093000
LOCATION:1CP Conference Room 4350
END:VEVENT
END:VCALENDAR
Dawson & Stenerson Standards Track [Page 137]
RFC 2445 iCalendar November 1998
The following is an example of an iCalendar object passed in a MIME
message with a single body part consisting of a "text/calendar"
Content Type.
TO:jsmith@host1.com
FROM:jdoe@host1.com
MIME-VERSION:1.0
MESSAGE-ID:<id3@host1.com>
CONTENT-TYPE:text/calendar
BEGIN:VCALENDAR
METHOD:xyz
VERSION:2.0
PRODID:-//ABC Corporation//NONSGML My Product//EN
BEGIN:VEVENT
DTSTAMP:19970324T1200Z
SEQUENCE:0
UID:uid3@host1.com
ORGANIZER:MAILTO:jdoe@host1.com
ATTENDEE;RSVP=TRUE:MAILTO:jsmith@host1.com
DTSTART:19970324T123000Z
DTEND:19970324T210000Z
CATEGORIES:MEETING,PROJECT
CLASS:PUBLIC
SUMMARY:Calendaring Interoperability Planning Meeting
DESCRIPTION:Discuss how we can test c&s interoperability\n
using iCalendar and other IETF standards.
LOCATION:LDB Lobby
ATTACH;FMTTYPE=application/postscript:ftp://xyzCorp.com/pub/
conf/bkgrnd.ps
END:VEVENT
END:VCALENDAR
The following is an example of a to-do due on April 15, 1998. An
audio alarm has been specified to remind the calendar user at noon,
the day before the to-do is expected to be completed and repeat
hourly, four additional times. The to-do definition has been modified
twice since it was initially created.
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//ABC Corporation//NONSGML My Product//EN
BEGIN:VTODO
DTSTAMP:19980130T134500Z
SEQUENCE:2
UID:uid4@host1.com
ORGANIZER:MAILTO:unclesam@us.gov
ATTENDEE;PARTSTAT=ACCEPTED:MAILTO:jqpublic@host.com
Dawson & Stenerson Standards Track [Page 138]
RFC 2445 iCalendar November 1998
DUE:19980415T235959
STATUS:NEEDS-ACTION
SUMMARY:Submit Income Taxes
BEGIN:VALARM
ACTION:AUDIO
TRIGGER:19980403T120000
ATTACH;FMTTYPE=audio/basic:http://host.com/pub/audio-
files/ssbanner.aud
REPEAT:4
DURATION:PT1H
END:VALARM
END:VTODO
END:VCALENDAR
The following is an example of a journal entry.
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//ABC Corporation//NONSGML My Product//EN
BEGIN:VJOURNAL
DTSTAMP:19970324T120000Z
UID:uid5@host1.com
ORGANIZER:MAILTO:jsmith@host.com
STATUS:DRAFT
CLASS:PUBLIC
CATEGORY:Project Report, XYZ, Weekly Meeting
DESCRIPTION:Project xyz Review Meeting Minutes\n
Agenda\n1. Review of project version 1.0 requirements.\n2.
Definition
of project processes.\n3. Review of project schedule.\n
Participants: John Smith, Jane Doe, Jim Dandy\n-It was
decided that the requirements need to be signed off by
product marketing.\n-Project processes were accepted.\n
-Project schedule needs to account for scheduled holidays
and employee vacation time. Check with HR for specific
dates.\n-New schedule will be distributed by Friday.\n-
Next weeks meeting is cancelled. No meeting until 3/23.
END:VJOURNAL
END:VCALENDAR
The following is an example of published busy time information. The
iCalendar object might be placed in the network resource
www.host.com/calendar/busytime/jsmith.ifb.
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//RDU Software//NONSGML HandCal//EN
BEGIN:VFREEBUSY
Dawson & Stenerson Standards Track [Page 139]
RFC 2445 iCalendar November 1998
ORGANIZER:MAILTO:jsmith@host.com
DTSTART:19980313T141711Z
DTEND:19980410T141711Z
FREEBUSY:19980314T233000Z/19980315T003000Z
FREEBUSY:19980316T153000Z/19980316T163000Z
FREEBUSY:19980318T030000Z/19980318T040000Z
URL:http://www.host.com/calendar/busytime/jsmith.ifb
END:VFREEBUSY
END:VCALENDAR
6 Recommended Practices
These recommended practices should be followed in order to assure
consistent handling of the following cases for an iCalendar object.
1. Content lines longer than 75 octets SHOULD be folded.
2. A calendar entry with a "DTSTART" property but no "DTEND"
property does not take up any time. It is intended to represent
an event that is associated with a given calendar date and time
of day, such as an anniversary. Since the event does not take up
any time, it MUST NOT be used to record busy time no matter what
the value for the "TRANSP" property.
3. When the "DTSTART" and "DTEND", for "VEVENT", "VJOURNAL" and
"VFREEBUSY" calendar components, and "DTSTART" and "DUE", for
"VTODO" calendar components, have the same value data type (e.g.,
DATE-TIME), they SHOULD specify values in the same time format
(e.g., UTC time format).
4. When the combination of the "RRULE" and "RDATE" properties on an
iCalendar object produces multiple instances having the same
start date/time, they should be collapsed to, and considered as,
a single instance.
5. When a calendar user receives multiple requests for the same
calendar component (e.g., REQUEST for a "VEVENT" calendar
component) as a result of being on multiple mailing lists
specified by "ATTENDEE" properties in the request, they SHOULD
respond to only one of the requests. The calendar user SHOULD
also specify (using the "MEMBER" parameter of the "ATTENDEE"
property) which mailing list they are a member of.
6. An implementation can truncate a "SUMMARY" property value to 255
characters.
Dawson & Stenerson Standards Track [Page 140]
RFC 2445 iCalendar November 1998
7. If seconds of the minute are not supported by an implementation,
then a value of "00" SHOULD be specified for the seconds
component in a time value.
8. If the value type parameter (VALUE=) contains an unknown value
type, it SHOULD be treated as TEXT.
9. TZURL values SHOULD NOT be specified as a FILE URI type. This URI
form can be useful within an organization, but is problematic in
the Internet.
10. Some possible English values for CATEGORIES property include
"ANNIVERSARY", "APPOINTMENT", "BUSINESS", "EDUCATION",
"HOLIDAY", "MEETING", "MISCELLANEOUS", "NON-WORKING HOURS", "NOT
IN OFFICE", "PERSONAL", "PHONE CALL", "SICK DAY", "SPECIAL
OCCASION", "TRAVEL", "VACATION". Categories can be specified in
any registered language.
11. Some possible English values for RESOURCES property include
"CATERING", "CHAIRS", "COMPUTER PROJECTOR", "EASEL", "OVERHEAD
PROJECTOR", "SPEAKER PHONE", "TABLE", "TV", "VCR", "VIDEO
PHONE", "VEHICLE". Resources can be specified in any registered
language.
7 Registration of Content Type Elements
This section provides the process for registration of MIME
Calendaring and Scheduling Content Type iCalendar object methods and
new or modified properties.
7.1 Registration of New and Modified iCalendar Object Methods
New MIME Calendaring and Scheduling Content Type iCalendar object
methods are registered by the publication of an IETF Request for
Comments (RFC). Changes to an iCalendar object method are registered
by the publication of a revision of the RFC defining the method.
7.2 Registration of New Properties
This section defines procedures by which new properties or enumerated
property values for the MIME Calendaring and Scheduling Content Type
can be registered with the IANA. Non-IANA properties can be used by
bilateral agreement, provided the associated properties names follow
the "X-" convention.
The procedures defined here are designed to allow public comment and
review of new properties, while posing only a small impediment to the
definition of new properties.
Dawson & Stenerson Standards Track [Page 141]
RFC 2445 iCalendar November 1998
Registration of a new property is accomplished by the following
steps.
7.2.1 Define the property
A property is defined by completing the following template.
To: ietf-calendar@imc.org
Subject: Registration of text/calendar MIME property XXX
Property name:
Property purpose:
Property value type(s):
Property parameter (s):
Conformance:
Description:
Format definition:
Examples:
The meaning of each field in the template is as follows.
Property name: The name of the property, as it will appear in the
body of an text/calendar MIME Content-Type "property: value" line to
the left of the colon ":".
Property purpose: The purpose of the property (e.g., to indicate a
delegate for the event or to-do, etc.). Give a short but clear
description.
Property value type (s): Any of the valid value types for the
property value needs to be specified. The default value type also
needs to be specified. If a new value type is specified, it needs to
be declared in this section.
Property parameter (s): Any of the valid property parameters for the
property needs to be specified.
Conformance: The calendar components that the property can appear in
needs to be specified.
Dawson & Stenerson Standards Track [Page 142]
RFC 2445 iCalendar November 1998
Description: Any special notes about the property, how it is to be
used, etc.
Format definition: The ABNF for the property definition needs to be
specified.
Examples: One or more examples of instances of the property needs to
be specified.
7.2.2 Post the Property definition
The property description MUST be posted to the new property
discussion list, ietf-calendar@imc.org.
7.2.3 Allow a comment period
Discussion on the new property MUST be allowed to take place on the
list for a minimum of two weeks. Consensus MUST be reached on the
property before proceeding to the next step.
7.2.4 Submit the property for approval
Once the two-week comment period has elapsed, and the proposer is
convinced consensus has been reached on the property, the
registration application should be submitted to the Method Reviewer
for approval. The Method Reviewer is appointed to the Application
Area Directors and can either accept or reject the property
registration. An accepted registration should be passed on by the
Method Reviewer to the IANA for inclusion in the official IANA method
registry. The registration can be rejected for any of the following
reasons. 1) Insufficient comment period; 2) Consensus not reached; 3)
Technical deficiencies raised on the list or elsewhere have not been
addressed. The Method Reviewer's decision to reject a property can be
appealed by the proposer to the IESG, or the objections raised can be
addressed by the proposer and the property resubmitted.
7.3 Property Change Control
Existing properties can be changed using the same process by which
they were registered.
1. Define the change
2. Post the change
3. Allow a comment period
4. Submit the property for approval
Dawson & Stenerson Standards Track [Page 143]
RFC 2445 iCalendar November 1998
Note that the original author or any other interested party can
propose a change to an existing property, but that such changes
should only be proposed when there are serious omissions or errors in
the published memo. The Method Reviewer can object to a change if it
is not backward compatible, but is not required to do so.
Property definitions can never be deleted from the IANA registry, but
properties which are no longer believed to be useful can be declared
OBSOLETE by a change to their "intended use" field.
8 References
[IMIP] Dawson, F., Mansour, S. and S. Silverberg, "iCalendar
Message-based Interoperability Protocol (IMIP)", RFC 2447,
November 1998.
[ITIP] Silverberg, S., Mansour, S., Dawson, F. and R. Hopson,
"iCalendar Transport-Independent Interoperability Protocol
(iTIP) : Scheduling Events, Busy Time, To-dos and Journal
Entries", RFC 2446, November 1998.
[ISO 8601] ISO 8601, "Data elements and interchange formats-
Information interchange--Representation of dates and
times", International Organization for Standardization,
June, 1988.
[ISO 9070] ISO/IEC 9070, "Information Technology_SGML Support
Facilities--Registration Procedures for Public Text Owner
Identifiers", Second Edition, International Organization
for Standardization, April 1991.
[RFC 822] Crocker, D., "Standard for the Format of ARPA Internet
Text Messages", STD 11, RFC 822, August 1982.
[RFC 1738] Berners-Lee, T., Masinter, L. and M. McCahill, "Uniform
Resource Locators (URL)", RFC 1738, December 1994.
[RFC 1766] Alvestrand, H., "Tags for the Identification of
Languages", RFC 1766, March 1995.
[RFC 2045] Freed, N. and N. Borenstein, " Multipurpose Internet Mail
Extensions (MIME) - Part One: Format of Internet Message
Bodies", RFC 2045, November 1996.
[RFC 2046] Freed, N. and N. Borenstein, " Multipurpose Internet Mail
Extensions (MIME) - Part Two: Media Types", RFC 2046,
November 1996.
Dawson & Stenerson Standards Track [Page 144]
RFC 2445 iCalendar November 1998
[RFC 2048] Freed, N., Klensin, J. and J. Postel, "Multipurpose
Internet Mail Extensions (MIME) - Part Four: Registration
Procedures", RFC 2048, January 1997.
[RFC 2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC 2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
[RFC 2279] Yergeau, F., "UTF-8, a transformation format of ISO
10646", RFC 2279, January 1998.
[RFC 2425] Howes, T., Smith, M. and F. Dawson, "A MIME Content-Type
for Directory Information", RFC 2425, September 1998.
[RFC 2426] Dawson, F. and T. Howes, "vCard MIME Directory Profile",
RFC 2426, September 1998.
[TZ] Olson, A.D., et al, Time zone code and data,
ftp://elsie.nci.nih.gov/pub/, updated periodically.
[VCAL] Internet Mail Consortium, "vCalendar - The Electronic
Calendaring and Scheduling Exchange Format",
http://www.imc.org/pdi/vcal-10.txt, September 18, 1996.
9 Acknowledgments
A hearty thanks to the IETF Calendaring and Scheduling Working Group
and also the following individuals who have participated in the
drafting, review and discussion of this memo:
Roland Alden, Harald T. Alvestrand, Eric Berman, Denis Bigorgne, John
Binici, Bill Bliss, Philippe Boucher, Steve Carter, Andre
Courtemanche, Dave Crocker, David Curley, Alec Dun, John Evans, Ross
Finlayson, Randell Flint, Ned Freed, Patrik Faltstrom, Chuck
Grandgent, Mark Handley, Steve Hanna, Paul B. Hill, Paul Hoffman,
Ross Hopson, Mark Horton, Daryl Huff, Bruce Kahn, C. Harald Koch,
Ryan Jansen, Don Lavange, Antoine Leca, Theodore Lorek, Steve
Mansour, Skip Montanaro, Keith Moore, Cecil Murray, Chris Newman,
John Noerenberg, Ralph Patterson, Pete Resnick, Keith Rhodes, Robert
Ripberger, John Rose, Doug Royer, Andras Salamar, Ted Schuh, Vinod
Seraphin, Derrick Shadel, Ken Shan, Andrew Shuman, Steve Silverberg,
William P. Spencer, John Sun, Mark Towfiq, Yvonne Tso, Robert Visnov,
James L. Weiner, Mike Weston, William Wyatt.
Dawson & Stenerson Standards Track [Page 145]
RFC 2445 iCalendar November 1998
10 Authors' and Chairs' Addresses
The following address information is provided in a MIME-VCARD,
Electronic Business Card, format.
The authors of this memo are:
BEGIN:VCARD
VERSION:3.0
N:Dawson;Frank
FN:Frank Dawson
ORG:Lotus Development Corporation
ADR;TYPE=WORK,POSTAL,PARCEL:;;6544 Battleford Drive;
Raleigh;NC;27613-3502;USA
TEL;TYPE=WORK,MSG:+1-919-676-9515
TEL;TYPE=WORK,FAX:+1-919-676-9564
EMAIL;TYPE=PREF,INTERNET:Frank_Dawson@Lotus.com
EMAIL;TYPE=INTERNET:fdawson@earthlink.net
URL:http://home.earthlink.net/~fdawson
END:VCARD
BEGIN:VCARD
VERSION:3.0
N:Stenerson;Derik
FN:Derik Stenerson
ORG:Microsoft Corporation
ADR;TYPE=WORK,POSTAL,PARCEL:;;One Microsoft Way;
Redmond;WA;98052-6399;USA
TEL;TYPE=WORK,MSG:+1-425-936-5522
TEL;TYPE=WORK,FAX:+1-425-936-7329
EMAIL;TYPE=INTERNET:deriks@Microsoft.com
END:VCARD
The iCalendar object is a result of the work of the Internet
Engineering Task Force Calendaring and Scheduling Working Group. The
chairmen of that working group are:
BEGIN:VCARD
VERSION:3.0
N:Ganguly;Anik
FN:Anik Ganguly
ORG: Open Text Inc.
ADR;TYPE=WORK,POSTAL,PARCEL:;Suite 101;38777 West Six Mile Road;
Livonia;MI;48152;USA
TEL;TYPE=WORK,MSG:+1-734-542-5955
EMAIL;TYPE=INTERNET:ganguly@acm.org
END:VCARD
Dawson & Stenerson Standards Track [Page 146]
RFC 2445 iCalendar November 1998
The co-chairman of that working group is:
BEGIN:VCARD
VERSION:3.0
N:Moskowitz;Robert
FN:Robert Moskowitz
EMAIL;TYPE=INTERNET:rgm-ietf@htt-consult.com
END:VCARD
Dawson & Stenerson Standards Track [Page 147]
RFC 2445 iCalendar November 1998
11. Full Copyright Statement
Copyright (C) The Internet Society (1998). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Dawson & Stenerson Standards Track [Page 148]
I'd like to thank everyone that ever helped me on the How to Use Revolution and Improve Revolution mailing list, without the community we would be nowhere. I started making a list of names, but it was growing to big and this stack is big enough already.
I'd like to thanks the RunRev team, they made coding fun again to me. I'd like to thanks those fine folks I met at Monterey last year, it was a very fun time. I'd like to thanks those that attend to the EuroRevDevConf in Malta, man that country rocks, I am making Hobz biz-zejt on a regular basis...
Also, I'd like to thank St. Peter for it was only due to his help and those two weeks without thunder storms frying my motherboard that I could work this library. (This G4 was toasted three times already... I have a whole graveyard of motherboards...)
Hope you guys like this thing. Andre Alves Garzia 5 de Abril de 2005 Niter—i, Brasil