| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |