Path: utzoo!attcan!uunet!ogicse!unicorn!blake!milton!whit
From: whit@milton.acs.washington.edu (John Whitmore)
Newsgroups: sci.electronics
Subject: Re: LAN speed?????
Summary: FDDI and RF modems are faster than Ethernet hardware
Keywords: Ethernet, cable, transmission line.
Message-ID: <2846@milton.acs.washington.edu>
Date: 13 Apr 90 06:11:26 GMT
References: <19603@boulder.Colorado.EDU> <7301@tekgvs.LABS.TEK.COM> <12581355675019@MATHOM.CISCO.COM>
Reply-To: whit@milton.acs.washington.edu (John Whitmore)
Organization: University of Washington, Seattle
Lines: 23


	There are busses (Futurebus+) that can transfer circa 250Mbytes/sec,
and fiber optic (FDDI) proposed hardware for higher throughput,
as well as RF modems (the campus here uses some) that can
get virtually the same throughput that a cable TV operation 
needs (about .5 Gbit/sec).  None of these, however, could
replace Ethernet.  Excepting Futurebus, they aren't supported 
through the ISO levels down to the message level (I think I got 
the right level; corrections gratefully accepted), so they are NOT networks.  
Futurebus has a length limitation (fifty feet?) that keeps it
from being a simple competitor.
	The Ethernet packet-delivery and collision sensing are
its beneficial features; if you need more throughput, offload 
devices from the trunk Ethernet and use a bridge to connect
them (i.e. faster Ethernet is equivalent to using more Ethernets).
There are many advantages to this approach (a blabby node doesn't
tie up everyone's Ethernet, an axe can't stop all traffic
for a mile radius, a local data source can be kept private from
listeners on other Ethernets), and the hardware manufacturers
like it, too! :->

 I am known for my brilliance,              John Whitmore
by those who do not know me well.