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45 lines
2.0 KiB
Plaintext
45 lines
2.0 KiB
Plaintext
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Linux X.25 Project
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As my third year dissertation at University I have taken it upon myself to
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write an X.25 implementation for Linux. My aim is to provide a complete X.25
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Packet Layer and a LAPB module to allow for "normal" X.25 to be run using
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Linux. There are two sorts of X.25 cards available, intelligent ones that
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implement LAPB on the card itself, and unintelligent ones that simply do
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framing, bit-stuffing and checksumming. These both need to be handled by the
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system.
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I therefore decided to write the implementation such that as far as the
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Packet Layer is concerned, the link layer was being performed by a lower
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layer of the Linux kernel and therefore it did not concern itself with
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implementation of LAPB. Therefore the LAPB modules would be called by
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unintelligent X.25 card drivers and not by intelligent ones, this would
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provide a uniform device driver interface, and simplify configuration.
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To confuse matters a little, an 802.2 LLC implementation for Linux is being
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written which will allow X.25 to be run over an Ethernet (or Token Ring) and
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conform with the JNT "Pink Book", this will have a different interface to
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the Packet Layer but there will be no confusion since the class of device
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being served by the LLC will be completely separate from LAPB. The LLC
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implementation is being done as part of another protocol project (SNA) and
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by a different author.
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Just when you thought that it could not become more confusing, another
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option appeared, XOT. This allows X.25 Packet Layer frames to operate over
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the Internet using TCP/IP as a reliable link layer. RFC1613 specifies the
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format and behaviour of the protocol. If time permits this option will also
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be actively considered.
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A linux-x25 mailing list has been created at vger.kernel.org to support the
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development and use of Linux X.25. It is early days yet, but interested
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parties are welcome to subscribe to it. Just send a message to
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majordomo@vger.kernel.org with the following in the message body:
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subscribe linux-x25
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end
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The contents of the Subject line are ignored.
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Jonathan
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g4klx@g4klx.demon.co.uk
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