0001 .. SPDX-License-Identifier: GPL-2.0
0002
0003 ==================
0004 Linux X.25 Project
0005 ==================
0006
0007 As my third year dissertation at University I have taken it upon myself to
0008 write an X.25 implementation for Linux. My aim is to provide a complete X.25
0009 Packet Layer and a LAPB module to allow for "normal" X.25 to be run using
0010 Linux. There are two sorts of X.25 cards available, intelligent ones that
0011 implement LAPB on the card itself, and unintelligent ones that simply do
0012 framing, bit-stuffing and checksumming. These both need to be handled by the
0013 system.
0014
0015 I therefore decided to write the implementation such that as far as the
0016 Packet Layer is concerned, the link layer was being performed by a lower
0017 layer of the Linux kernel and therefore it did not concern itself with
0018 implementation of LAPB. Therefore the LAPB modules would be called by
0019 unintelligent X.25 card drivers and not by intelligent ones, this would
0020 provide a uniform device driver interface, and simplify configuration.
0021
0022 To confuse matters a little, an 802.2 LLC implementation is also possible
0023 which could allow X.25 to be run over an Ethernet (or Token Ring) and
0024 conform with the JNT "Pink Book", this would have a different interface to
0025 the Packet Layer but there would be no confusion since the class of device
0026 being served by the LLC would be completely separate from LAPB.
0027
0028 Just when you thought that it could not become more confusing, another
0029 option appeared, XOT. This allows X.25 Packet Layer frames to operate over
0030 the Internet using TCP/IP as a reliable link layer. RFC1613 specifies the
0031 format and behaviour of the protocol. If time permits this option will also
0032 be actively considered.
0033
0034 A linux-x25 mailing list has been created at vger.kernel.org to support the
0035 development and use of Linux X.25. It is early days yet, but interested
0036 parties are welcome to subscribe to it. Just send a message to
0037 majordomo@vger.kernel.org with the following in the message body:
0038
0039 subscribe linux-x25
0040 end
0041
0042 The contents of the Subject line are ignored.
0043
0044 Jonathan
0045
0046 g4klx@g4klx.demon.co.uk
