1 Linux X.25 Project
2
3 As my third year dissertation at University I have taken it upon myself to
4 write an X.25 implementation for Linux. My aim is to provide a complete X.25
5 Packet Layer and a LAPB module to allow for "normal" X.25 to be run using
6 Linux. There are two sorts of X.25 cards available, intelligent ones that
7 implement LAPB on the card itself, and unintelligent ones that simply do
8 framing, bit-stuffing and checksumming. These both need to be handled by the
9 system.
10
11 I therefore decided to write the implementation such that as far as the
12 Packet Layer is concerned, the link layer was being performed by a lower
13 layer of the Linux kernel and therefore it did not concern itself with
14 implementation of LAPB. Therefore the LAPB modules would be called by
15 unintelligent X.25 card drivers and not by intelligent ones, this would
16 provide a uniform device driver interface, and simplify configuration.
17
18 To confuse matters a little, an 802.2 LLC implementation for Linux is being
19 written which will allow X.25 to be run over an Ethernet (or Token Ring) and
20 conform with the JNT "Pink Book", this will have a different interface to
21 the Packet Layer but there will be no confusion since the class of device
22 being served by the LLC will be completely separate from LAPB. The LLC
23 implementation is being done as part of another protocol project (SNA) and
24 by a different author.
25
26 Just when you thought that it could not become more confusing, another
27 option appeared, XOT. This allows X.25 Packet Layer frames to operate over
28 the Internet using TCP/IP as a reliable link layer. RFC1613 specifies the
29 format and behaviour of the protocol. If time permits this option will also
30 be actively considered.
31
32 A linux-x25 mailing list has been created at vger.kernel.org to support the
33 development and use of Linux X.25. It is early days yet, but interested
34 parties are welcome to subscribe to it. Just send a message to
35 majordomo@vger.kernel.org with the following in the message body:
36
37 subscribe linux-x25
38 end
39
40 The contents of the Subject line are ignored.
41
42 Jonathan
43
44 g4klx@g4klx.demon.co.uk
This page was automatically generated by the
LXR engine.
Visit the LXR main site for more
information.