1Linux X.25 Project
   3As my third year dissertation at University I have taken it upon myself to
   4write an X.25 implementation for Linux. My aim is to provide a complete X.25
   5Packet Layer and a LAPB module to allow for "normal" X.25 to be run using
   6Linux. There are two sorts of X.25 cards available, intelligent ones that
   7implement LAPB on the card itself, and unintelligent ones that simply do
   8framing, bit-stuffing and checksumming. These both need to be handled by the
  11I therefore decided to write the implementation such that as far as the
  12Packet Layer is concerned, the link layer was being performed by a lower
  13layer of the Linux kernel and therefore it did not concern itself with
  14implementation of LAPB. Therefore the LAPB modules would be called by
  15unintelligent X.25 card drivers and not by intelligent ones, this would
  16provide a uniform device driver interface, and simplify configuration.
  18To confuse matters a little, an 802.2 LLC implementation for Linux is being
  19written which will allow X.25 to be run over an Ethernet (or Token Ring) and
  20conform with the JNT "Pink Book", this will have a different interface to
  21the Packet Layer but there will be no confusion since the class of device
  22being served by the LLC will be completely separate from LAPB. The LLC
  23implementation is being done as part of another protocol project (SNA) and
  24by a different author.
  26Just when you thought that it could not become more confusing, another
  27option appeared, XOT. This allows X.25 Packet Layer frames to operate over
  28the Internet using TCP/IP as a reliable link layer. RFC1613 specifies the
  29format and behaviour of the protocol. If time permits this option will also
  30be actively considered.
  32A linux-x25 mailing list has been created at to support the
  33development and use of Linux X.25. It is early days yet, but interested
  34parties are welcome to subscribe to it. Just send a message to with the following in the message body:
  37subscribe linux-x25
  40The contents of the Subject line are ignored.
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