Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!ucsd!ucbvax!GATEWAY.MITRE.ORG!barns
From: barns@GATEWAY.MITRE.ORG (Bill Barns)
Newsgroups: comp.protocols.iso
Subject: Re:  How to connect ISs in Gosip 2.0?
Message-ID: <8910240116.AA20455@gateway.mitre.org>
Date: 24 Oct 89 01:16:15 GMT
Sender: usenet@ucbvax.BERKELEY.EDU
Organization: The Internet
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After I pestered Dallas Scott and Paul Tsuchiya about this, we checked
some of the standards and concluded that the "right" OSI way for two
IS's to talk over a point-to-point subnetwork (yes, such a link is a
subnetwork!) when using ISO 8473 is to use a direct embedding in ISO
7776 (HDLC).  This is described in ISO 8880-3 near the end of the
document.  We deem it an error of GOSIP 2.0 not to recognize this.
Whether NIST agrees, we do not yet know.

There are, of course, certain difficulties in using mixed ISO and
non-ISO stacks in this environment.  This problem conld be circumvented
legally by using X.25, or deviously (but perhaps still legally) by
assigning HDLC addresses for the non-OSI protocols that are other than
the ones defined by ISO and CCITT for the "legitimate" uses of HDLC.
At the moment, in the case of IP, you can also disambiguate on the
first octet as you would do with the various OSI network layer
protocols.

Bill Barns / MITRE-Washington / barns@gateway.mitre.org