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