CCN-lite, a lightweight implementation of the CCNx protocol and its variations
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README.md

Status of Automatic Tests

Build Status

(Currently, CCN-lite V2 supports only automatic build testing, there are no functionality tests)

Overview

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CCN-lite is a reduced and lightweight -- yet functionally interoperable -- implementation of the CCNx and NDN protocols. It covers:

CCN-lite supports multiple platforms, including:

  • Linux and OS X user space
  • Linux kernel
  • Android
  • RIOT OS

CCN-lite is meant as a code base for class room work, experimental extensions and simulation experiments. The ISC license makes it an excellent starting point for commercial products.

CCN-lite has been included in the RIOT operating system for the Internet of Things (IoT): http://www.riot-os.org/

Table of Contents

  1. Getting started
  2. Rationale for CCN-lite
  3. Extensions
  4. CCN-lite supported platforms
  5. Command line tools
  6. Useful links
  7. Tentative roadmap
  8. Changelog
  9. Credits

1. Getting started

To start right now with CCN-lite visit the tutorial. It covers installation on Unix and basic functionality of CCN-lite.

For more information about CCN-lite supported platforms and how to build, see CCN-lite supported platforms. The source code of CCN-lite is available on GitHub, either the master branch or dev-master. If you found a bug or want to report a problem with CCN-lite, feel free to create an issue on GitHub - we appreciate it!

2. Rationale for CCN-lite

The original motivation in 2011 for creating CCN-lite was that PARC's CCNx router software had grown huge. CCN-lite provides a lean alternative for educational purposes and as a stepping stone. It's for those who want a simple piece of software for experimentation or own development, but who do not need all features of the full thing.

This brings the interesting question of interoperability: What minimum functionality is necessary in order to participate in a CCNx network? With CCN-lite, we have made a first attempt at identifying that set, but we are aware that this set might be incomplete, or may change depending on how CCNx evolves. We consider this question of "sufficient CCNx functionality" to be of engineering and academic interest of its own and welcome contributions from everybody.

Hence, with CCN-lite, we did a race-to-the-bottom and strived for a kind of "Level-0" interoperability. Level-0, as we understood it, covers:

  • ccnb encoding of messages (or any other encoding flavor, including the TLV variants)
  • PIT and FIB, basic CCN data structures
  • longest and exact prefix matching for basic CCN operations, including minsuffixcomp und maxsuffixcomp handling
  • matching of publisher's public key to fight cache poisoning
  • nonce and/or hop limit tracking to avoid loops as a minimal safeguard

As an interoperability goal we set for ourselves the threshold that the CCN-lite software must be able to route at the CCN level between fully fledged CCNx forwarders. Of course, this is a moving target, but we regularly use our tools to interface with the NDN testbed, for example.

We deliberately do not cover in our CCN-lite code:

  • sophisticated data structures for performance optimizations
  • exclusion filtering in interests
  • all TCP connectivity and the old CCNx cmd line utilities that have TCP hardwired into them
  • crypto functionality which is not our prime concern (yet)
  • repository functionality, SYNC server, ...

A second reason to create CCN-lite was the software license (the original CCNx project picked GNU, but NDN also has chosen this path) where we prefer a Berkeley Software Distribution style of "do whatever you want" as we believe that this will help adopting CCN technology. Therefore, CCN-lite is released under the ISC license. We have learned that several companies have picked up CCN-lite for their internal experiments, so we think our license choice was right.

What you get with CCN-lite is:

  • a tiny core and forwarder
  • multiple platform support
  • little memory usage, runs on IOT platforms with less than 10k ram
  • libraries for applications (e.g. packet encoding libraries)
  • partially interoperable management protocol implementation
  • a simple HTTP server to display the relay's internal configuration
  • plus some interesting extensions of our own, see the next section.
  • little dependencies: cmake and openssl

3. Extensions

In several selected areas we have started our own contributions that are now part of CCN-lite:

  • Experimental RPC functionality for letting neighbors mutually invoke functions, which could be the starting point both for network management functionality and for data marshalling (of interests and data objects) using the TLV encoding.

  • Clean packet scheduler support at chunk level as well as packet or fragment level (symbol USE_SCHEDULER)

  • Packet fragmentation and lost packet detection support for running the CCNx protocol natively over Ethernet (symbol USE_FRAG). This is somehow outdated and waits for protocol specs to emerge.

Other features that you can switch on and off at compile time are:

Featue Description
USE_CCNxDIGEST Enable digest component, requires crypto lib.
USE_CHEMFLOW Experimental scheduler based on chemical networking, source not included.
USE_DEBUG Basic data structure dumping.
USE_DEBUG_MALLOC Compile with memory armoring.
USE_DUP_CHECK Check for duplicate nonces.
USE_ECHO Enable an echo prefix, returning the current time.
USE_LINKLAYER Talk to Ethernet, W-LAN, 802.15.4 devices, raw frames.
USE_FRAG Enable fragments, to run CCNx over Ethernet.
USE_HMAC256 Enables hash-based message authentication codes.
USE_HTTP_STATUS Provide status info for web browsers.
USE_IPV4 Enable IP support.
USE_LOGGING Enable log messages.
USE_KITE Routing along the return path, not yet supported.
USE_MGMT React to CCNx management protocol messages.
USE_SCHEDULER Rate control at CCNx msg and fragment level.
USE_SIGNATURES Authenticate management messages.
USE_STATS Enable statistics.
USE_SUITE_* Enable a specific protocol: CCNB, NDNTLV (NDN 2014), CCNTLV (CCNx2014), or LOCALRPC and COMPRESSED (for packet compression)
USE_UNIXSOCKET Add UNIX IPC to the set of interfaces.

The approach for these extensions is that one can tailor a CCN forwarder to including only those features really necessary. We have strived to make these choices as orthogonal as possible and invite you to attempt the same for your additions.

4. CCN-lite supported platforms and how to compile

CCN-lite currently supports five platforms. To find out how to install and use CCN-lite on each individual platform, refer to the platform-specific readme files:

Additionally, CCN-lite has a pre-built Dockerfile to enable the usage of Docker with CCN-lite. See the Docker-specific readme file for more information.

5. Command line tools

The commandline tools can be found in the ccnl-utils folder The main command line tools and their corresponding source file that are shipped with CCN-lite are the following:

Tool Description
ccn-lite-relay CCN-lite forwarder: user space.
ccn-lite-lxkernel CCN-lite forwarder: Linux kernel module
ccn-lite-ctrl Command line program running the CCNx management protocol (over Unix sockets). Used for configuring a running relay either running in user space or as a kernel module.
ccn-lite-ccnb2xml Simple CCNB packet parser
ccn-lite-cryptoserver Used by the kernel module to carry out compute intensive crypto operations in user instead of kernel space.
ccn-lite-fetch Fetches both a single chunk content or a series of chunks for larger named data. Only the content is returned without any protocol bytes.
ccn-lite-mkC Simple content composer, to stdout, without crypto.
ccn-lite-mkF Simple tool to split a large file into a fragment series.
ccn-lite-mkI Simple interest composer, to stdout.
ccn-lite-peek Simple interest injector waiting for a content chunk.
ccn-lite-pktdump Powerful packet dumper for all known packet formats. Output is in hexdump style, XML or content only.
ccn-lite-produce Creates a series of chunks for data that does not fit into a single PDU.
ccn-lite-rpc Send an RPC request and return the reply.
ccn-lite-valid Demo application for validating a packet's signature.

6. Links:

8. Changelog

Release 2.0.1 beta (Jun 2018)

  • Last NFN Release, further versions will not contain NFN, see FAQ
  • Add: Documentation
  • Bugfixes
  • CVE patches
  • Removed unused IOTTLV and CISTLV Packet formats.

Release 2.0.0 beta (Nov 2017)

  • Restructuration of the Code to a library system Code was split to following libraries:
    • ccnl-core: basic data structures
      • ccnl-fwd: forwarding functionality of CCN-lite
      • ccnl-pkt: packet encoding library, can be used for end point application with no forwarding requirements
      • ccnl-riot: RIOT integration library
  • change build system to cmake
  • add further RIOT support - add compressed packet format in an early stage
  • Fix a lot of Bugs
  • Fix some CVEs (discovered by Eric Sesterhenn / X41 D-Sec): CVE-2017-12412, CVE-2017-12464, CVE-2017-12465, CVE-2017-12466, CVE-2017-12467, CVE-2017-12468, CVE-2017-12469, CVE-2017-12471, CVE-2017-12472

Release 0.3.0 (Jul 2015)

  • Demonstrated interoperability with now-stabilized CCNx1.0, which can run side-by-side with NDN in a single CCN-lite relay
  • OMNeT++ integration is back, as it has been requested many times
  • New platforms and transport:
    • Arduino and RFduino
    • Android and Bluetooth Low Energy
  • New functionality: "begin-end" fragmentation for CCNx1.0 and NDN
  • Improved build quality for Ubuntu and OSX
  • Improved READMEs all over the release, easy tutorials
  • Named Function Networking (NFN) over NDN now has Python bindings to make the publishing of named functions easier.

9. Credits

Release 2.0.1 beta (Jun 2018)

Code contributions:

Michael Frey (MSA Safety)
Cenk Gündogan (HAW Hamburg)
Eric Sesterhenn (X41-DSec)
Peter Kietzmann (HAW Hamburg)
Martine Lenders (FU Berlin)
Claudio Marxer (Uni Basel)
Dima Mansour (Uni Basel)
Urs Schnurrenberger (Uni Basel)
Christian Tschudin (Uni Basel)
Christopher Scherb (Uni Basel)

Release 2.0.0 beta (Nov 2017)

Code contributions:

Christopher Scherb
Balazs Faludi
Claudio Marxer
Cenk Gündogan
Eric Sesterhenn
Christian F. Tschudin

Release 0.3.0 (Jul 2015)

Code contributions:

Lukas Beck
Christopher Scherb
Manolis Sifalakis
Christian F. Tschudin

Feedback and other contributions:

Fateh Al-Mufti
Frederik Brix
Patrick Buder
Daniel Federau
Ilir Fetai
Nenad Kokeza
David Kordsmeier
Dima Mansour
Marc Mosko
Mihai Daniel Rapcea
Fabian Rauschenbach
Yanick Salzmann
Maarten Schenk
Urs Schnurrenberger
Marco Suter
Marc-Andrea Tarnutzer
Marco Dieter Vogt
Akan Yilmaz

Release 0.2.0 (Dec 2014)

Code contributions:

Basil Kohler
Christian Mehlis
Massimo Monti
Christopher Scherb
Manolis Sifalakis
Christian F. Tschudin

Code and documentation feedback:

Samuel Bader
Christoph Betschart
Nore Derguti
Ralph Droms
Wilson A. Eghonghon
Daniel Federau
Ralph Gasser
Cedric Geissmann
Rasa Liebfried
Dario Maggi
Frank Müller
Marko Obradovic
Michaja Pressmar
Mihai D. Rapcea
Urs Schnurrenberger
Thomas Simonsen
Alexander Stiemer
Ziba Tavassoli
Simon Wang
Mario Weber

Release 0.1.0 (Jul 2013)

Code contributions:

Stefan Braun
Pierre Imai
Basil Kohler
Thomas Meyer
Massimo Monti
Christopher Scherb
Manolis Sifalakis
Christian F. Tschudin