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 is also possible 23which could allow X.25 to be run over an Ethernet (or Token Ring) and 24conform with the JNT "Pink Book", this would have a different interface to 25the Packet Layer but there would be no confusion since the class of device 26being served by the LLC would be completely separate from LAPB. 27 28Just when you thought that it could not become more confusing, another 29option appeared, XOT. This allows X.25 Packet Layer frames to operate over 30the Internet using TCP/IP as a reliable link layer. RFC1613 specifies the 31format and behaviour of the protocol. If time permits this option will also 32be actively considered. 33 34A linux-x25 mailing list has been created at vger.kernel.org to support the 35development and use of Linux X.25. It is early days yet, but interested 36parties are welcome to subscribe to it. Just send a message to 37majordomo@vger.kernel.org with the following in the message body: 38 39subscribe linux-x25 40end 41 42The contents of the Subject line are ignored. 43 44Jonathan 45 46g4klx@g4klx.demon.co.uk 47