Copyright (C) 1998 WIDE Project.  All rights reserved.
Copyright (C) 1999,2000,2001,2002 University of Tromso.  All rights reserved.
Copyright (C) 2002 Invenia Innovation AS. All rights reserved.

*** Acknowledgements ***

Thanks to 6Net (EU project IST-2001-32603), http://www.6net.org/, for 
partially funding totd development. See also:

    http://cordis.europa.eu/search/index.cfm?fuseaction=result.document&RS_LANG=IT&RS_RCN=8495872&q=

Thanks to Telenor FoU, Tromsø for funding of and collaboration in
building our IPv6-only wireless MAN infrastructure.

Thanks to the Kame project (http://www.kame.net), and Itojun Hagino
in particular, for bugfixes and patches and the support for scoped
address rewriting.

Thanks to Nathan Lutchansky for adding Linux support.
Thanks to Simon Leinen for making totd work on Solaris.

And finally, thanks to those that reported bugs or requested features.

*** What does totd do? ***

Totd is a small DNS proxy nameserver that supports IPv6 only hosts/networks
that communicate with the IPv4 world using some translation mechanism. 
Examples of such translation mechanisms currently in use are: 

   * IPv6/IPv4 Network Address and Packet Translation (NAT-PT)
     implemented.
   * Transport level translators as the faithd implemented by 
     the KAME project (http://www.kame.net). See faithd(8) on
     *BSD/Kame.

These translators translate map IPv4 to IPv6 connections and back in some
way. In order for an application to connect through such a translator to
the world beyond it needs to use fake or fabricated addresses that are
routed to this translator. These fake addresses don't exist in the DNS,
and most likely you would not want them to appear there either. Totd
fixes this problem for now (until more elegant solutions emerge?) by
translating DNS queries/responses for the faked addresses. totd constructs
these fake addresses based on a configured IPv6 translator prefix and
records it *does* find in DNS. Totd is merely a stateless DNS-proxy, not 
a nameserver itself. Totd needs to be able to forward requests to a real 
nameserver. Recently, a running totd can be (re-)configured remotely
using http; see the INSTALL document for more information about this.

*** Some other experimental things you could use totd for ***

Totd can do some things that are more experimental. you can select at
compile time whether you want these or not. Totd supports re-writing of scoped
addresses in DNS responses and supports reverse namelookup for 6to4 names.
Scoped address rewriting is explained in the totd manual page.

6to4 reverse lookup is based on draft-moore-6to4-dns-00.txt, 
section 3.3:

     When such a resolver received a PTR or NS query for a label that
had a [x2002].IP6.ARPA suffix, it would first attempt to satisfy that
query from its cache, or failing that, by forwarding the query to an
upstream server.  If that query failed due to a "no such domain" error,
the resolver would then attempt to find the server for the
{something}.[x2002].IP6.ARPA label by issuing an NS query for
{something}.IN-ADDR.ARPA.

     If the original query was for PTR records, and one or more NS
records were found for {something}.IN-ADDR.ARPA, the resolver would then
forward the original query for {something}.[x2002].IP6.ARPA to one or
more of those servers, and return the results from one of the forwarded
queries if any were successful.

     If the original query was for NS records, and one or more NS
records were found for {something}.IN-ADDR.ARPA, the resolver would then
return the pseudo-records corresponding to the IN-ADDR.ARPA domains.
Those pseudo-records would NOT be marked as authoritative, and the
resolver would NOT cache those records.

*** Contacting the Author ***

You can contact me (Feico Dillema) at feico at dillema.net (s/ at /@).