[comp.protocols.appletalk] Unix Appletalk Bridge

cck@CUNIXC.CC.COLUMBIA.EDU (Charlie C. Kim) (10/13/88)

WARNING: THE FOLLOWING DESCRIBES EXPERIMENTAL SOFTWARE THAT IS NOT
MEANT FOR ANY SORT OF GENERAL DISTRIBUTION OR USE.

The Unix AppleTalk Bridge (uab) allows certain unix systems to act as
AppleTalk Bridges.  uab can be functionally divided into two parts.
The first is the actual AppleTalk Bridge implementation and the second
are the routines that define particular "Link Access Protocols" (aka
"hardware" delivery methods e.g. EtherTalk).  uab also supports an
internal demultiplexing that allows packets delivered to the uab node
to be delivered to other processes within that system.

Currently, uab runs on Ultrix 1.2 (and beyond) and SunOS 4.0 and
supports EtherTalk.  Unfortunately, with the current definition of
KIP's UDP encapsulation and delivery rules, it is not feasible to
implement KIP.  The only internal packet delivery mechanism defined is
a modified version of KIP's UDP encapsulation (modified-KIP) that uses
a different UDP port range over the internal loopback; thus CAP
programs must be relinked with a different low level delivery
mechanism to work with uab.  Note that all packets for these programs
are sent and received through the uab process.

Since uab does not understand KIP, it is necessary to have an
AppleTalk Bridge that understands both KIP encapsulation and EtherTalk
before KIP based "systems" (e.g. programs compiled with CAP, bridges
that only speak KIP on the ethernet interface--revisions of KIP before
2/88, etc) can work with uab's modified-KIP based programs.

This software is being distributed to encourage development of better
internal delivery mechanisms and alternate lap methods.

This software requires CAP libraries and include files.

uab, in the current form, is meant only for those who have a solid
understanding of the AppleTalk protocols in relation to AppleTalk
bridges (documented in Inside AppleTalk).  uab is NOT meant for
general distribution or use and questions relating to such will
probably be ignored.  The current distribution of uab is meant for
developers to try out.

uab is Copyright 1988 by The Trustees of Columbia University in the
City of New York.

To retrieve uab, use anonymous ftp to connect to
cunixc.cc.columbia.edu (128.59.40.130).  Retrieve uab.shar in the
directory uab.

Charlie C. Kim
Academic Computing and Communications Group
Center for Computing Activities
Columbia University

rich@sendai.sendai.ann-arbor.mi.us (K. Richard Magill) (08/12/89)

I'd like very much to talk to anyone who's got it running at all, much
less on a decstation.
--
rich.