Re: [ethereal-dev] LAPB/X.25 patch

[Guy Harris <gharris@xxxxxxxxxxxx>]

> I've been working on LAPB and X.25 dissectors for some time now. It
> seems to work fine for me so I'm sending a patch with my code to the
> list.

OK, I've checked it in.

> - add a LAPB dissector (normal LAPB only, no support for extended LAPB)

As I remember, IEEE 802.2/ISO 8022 LLC has somewhat of an SDLC flavor to
it, just like LAP[A-Z], ADCCP, and so on, so we may be able to combine
some of the LLC dissection and the LAPB dissection into common code that
could, conceivably be used for other SDLC-flavored protocols.

> - add a X.25 dissector. It currently only works with modulo 8 packets,
> because the only documentation I have about X.25 comes from Transpac
> (french X.25 network), which seems to use modulo 8 only. If someone can
> send me documentation about modulo 128 packets format, I will work on
> it.

It looks as if

	http://www.acacia-net.com/Clarinet/Protocol/x25l3ld0.htm

discusses at least some of the difference between LAPB in basic (modulo
8) form and extended (modulo 128) form; the page above it at

	http://www.acacia-net.com/Clarinet/protocol.htm

also has a bunch of links to packet layout information for X.25 stuff
above LAPB, which might discuss how modulo 8 and modulo 128 differ (I
infer from your mentioning modulo 8 and modulo 128 when talking about
X.25, not LAPB, that the X.25 layers above LAPB are also affected).

(Another site with protocol information is

	http://www.protocols.com/

which is run by RADCOM.)