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From: mouse@mcgill-vision.UUCP
Newsgroups: comp.dcom.lans
Subject: Re: Ethernet Compatibility...
Message-ID: <654@mcgill-vision.UUCP>
Date: Fri, 13-Feb-87 02:07:12 EST
Article-I.D.: mcgill-v.654
Posted: Fri Feb 13 02:07:12 1987
Date-Received: Sun, 15-Feb-87 04:38:16 EST
References: <4312@columbia.UUCP>
Organization: McGill University, Montreal
Lines: 30

In article <4312@columbia.UUCP>, desimone@tom.columbia.edu (Sal Desimone) writes:
> Hi...We've been successfully running an ethernet LAN here for the
> past couple of years.  [...] Since our network is a few years old,
> some of our hardware was designed according to the original ethernet
> standard (Version 1) and some according to Version 2.

We have an Ethernet here linking a two VAXen and a bunch of Suns.
Initially, the Suns had version 1 transcievers and the VAXen had
version 2 transcievers.  The results were a great slowdown when
speaking between incompatible transcievers.  Initially we just thought
it was a slow net, but when rdumps would lose the connection halfway
through we had to do some investigation.

The effect was that only one packet in N (N unknown) would get through.
Eventually enough packets in a row would be dropped and the connection
would time out.  It is a tribute to the robustness of TCP that the only
visible effects were occaisonal timeouts and (always) slow transfers.

We got version 2 transcievers for the Suns and the problem went away,
apparently for good.

So....don't expect good results when trying to make version 1 and
version 2 talk to one another.

					der Mouse

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