[comp.protocols.appletalk] Interpretation of ATP headers/user-bytes?

chudley@canon.co.uk (Martin Chudley) (02/07/91)

I'm writing a simple(!) AppleTalk packet displaying program which tries to
show meaningful information about packets picked up by the peek program.

I've studied "Inside AppleTalk" and bits of the CAP sources but I'm still
confused about how to recognise the different types of protocols carried
by ATP.   ZIP (GetZoneList, GetLocalZones, GetZoneListReply,
GetLocalZonesReply, GetMyZone, GetMyZoneReply), PAP and ASP.

There seems to be no way to interpret the data after the TID from the packet
alone, so I guess I need more context ie. knowledge of earlier ATP transactions,
yes?

"Inside AppleTalk" seems to hint that the ZIP stuff can be detected by certain
ATP control information and source or destination socket number 6.  If this is
the case, isn't it a bit of a kludge?

Thanks for any help

--
Martin Chudley						     chudley@canon.co.uk
   Canon Research Centre Europe, Surrey Research Park, Guildford, Surrey. UK
-- 
Martin Chudley (Postmaster)

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