Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!decwrl!sgi!vjs@rhyolite.wpd.sgi.com
From: vjs@rhyolite.wpd.sgi.com (Vernon Schryver)
Newsgroups: comp.dcom.lans
Subject: Re: Ethernet alternative needed
Message-ID: <43037@sgi.sgi.com>
Date: 14 Oct 89 19:01:26 GMT
References: <9478@zodiac.ADS.COM> <2406@umbc3.UMBC.EDU>
Sender: vjs@rhyolite.wpd.sgi.com
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Organization: Silicon Graphics, Inc., Mountain View, CA
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In article <2406@umbc3.UMBC.EDU>, chimiak@umbc3.UMBC.EDU (Mr. William J. Chimiak ) writes:
> 
> It seems to me that you are just implementing an FDDI concentrator....

An FDDI concentrator would require all existing ethernet stations to do
802.3 instead of ethernet.  Since essentially no machines on ethernets use
802.3, that would be a problem.

There is lots of talk about ether-to-FDDI bridges in the standards
committees.  However, there are some very big problems such as thru-put and
the >4KByte MTU on FDDI.

The original author's requirements might be met by one of the FDDI
"tunnels" for ethernet.  I think someone like Fibercom makes such devices.
(Please excuse me if they don't or if others also do.)

An FDDI-to-ether IP router might work.  For example, you could buy one
of the products shown at Interop to gateway between ether and fiber.

As I understand "ethernet fiber repeaters" and "ethernet fiber transcievers",
they have nothing to do with FDDI, except perhaps the fiber itself.  Even the
fiber connectors differ (ST's vs. MIC's).  An number of companies make them
and lots of places are now using them.  They may be what the original
author was thinking of.


Vernon Schryver
Silicon Graphics
vjs@sgi.com