1.. SPDX-License-Identifier: GPL-2.0 2 3================== 4Linux X.25 Project 5================== 6 7As my third year dissertation at University I have taken it upon myself to 8write an X.25 implementation for Linux. My aim is to provide a complete X.25 9Packet Layer and a LAPB module to allow for "normal" X.25 to be run using 10Linux. There are two sorts of X.25 cards available, intelligent ones that 11implement LAPB on the card itself, and unintelligent ones that simply do 12framing, bit-stuffing and checksumming. These both need to be handled by the 13system. 14 15I therefore decided to write the implementation such that as far as the 16Packet Layer is concerned, the link layer was being performed by a lower 17layer of the Linux kernel and therefore it did not concern itself with 18implementation of LAPB. Therefore the LAPB modules would be called by 19unintelligent X.25 card drivers and not by intelligent ones, this would 20provide a uniform device driver interface, and simplify configuration. 21 22To confuse matters a little, an 802.2 LLC implementation for Linux is being 23written which will allow X.25 to be run over an Ethernet (or Token Ring) and 24conform with the JNT "Pink Book", this will have a different interface to 25the Packet Layer but there will be no confusion since the class of device 26being served by the LLC will be completely separate from LAPB. The LLC 27implementation is being done as part of another protocol project (SNA) and 28by a different author. 29 30Just when you thought that it could not become more confusing, another 31option appeared, XOT. This allows X.25 Packet Layer frames to operate over 32the Internet using TCP/IP as a reliable link layer. RFC1613 specifies the 33format and behaviour of the protocol. If time permits this option will also 34be actively considered. 35 36A linux-x25 mailing list has been created at vger.kernel.org to support the 37development and use of Linux X.25. It is early days yet, but interested 38parties are welcome to subscribe to it. Just send a message to 39majordomo@vger.kernel.org with the following in the message body: 40 41subscribe linux-x25 42end 43 44The contents of the Subject line are ignored. 45 46Jonathan 47 48g4klx@g4klx.demon.co.uk 49