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From: cmsedore@cattle.maxwell.syr.edu (Christopher M Sedore)
Newsgroups: comp.os.386bsd.questions,comp.os.386bsd.development
Subject: Re: ethernet throughput
Date: 01 Mar 1995 00:10:28 GMT
Organization: Syracuse University, Syracuse NY, USA
Lines: 31
Message-ID: <CMSEDORE.95Feb28191028@cattle.maxwell.syr.edu>
References: <3it7m8$o39@clavin.uprc.com> <3itrg4$pfj@crl9.crl.com>
NNTP-Posting-Host: cattle.maxwell.syr.edu
In-reply-to: ggrant@crl.com's message of 27 Feb 1995 16:41:40 -0800

In article <3itrg4$pfj@crl9.crl.com> ggrant@crl.com (Gary E. Grant) writes:


[...]
   If they got 4 megabytes per second, It's not Ethernet.  Ethernet is 
   spec'ed at 10 Megabits per second which translates to 1.25 or less Megabytes
   per second, assuming perfect operation and no collisions and no overhead...

   in reality , due to CS/MA gaussian backoff, a normal ethernet cable 
   saturates at about 3.5 Megabits per second... or 450-500 KBytes per second..

This is nonsense.  I have more than a few ethernets which continuosly
deliver ~700k/s.  You can sustain ~1 megabyte/second over ethernet
with a pair of 486-66s running freebsd.

   Thats all you can get from thinwire/thickwire ethernet... Token ring is a 
   nonsaturating protocol It gets about 16 Megabits /second or 1.8-2.0 
   megabytes per second ...  

   The next thing faster is FDDI which is 125 Megabites or about 12 
   Megabytes/Second... BTW FDDI is a tokenring type of protocol ...
   comes in two flavors (Copper and Fiberoptic)

FDDI only has 100 megabits/s available for moving packet data, the rest
is eaten by signalling.

-Chris