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Path: utzoo!watmath!clyde!burl!ulysses!allegra!mit-eddie!godot!harvard!seismo!hao!ward
From: ward@hao.UUCP (Mike Ward)
Newsgroups: net.lan
Subject: Ethernet query
Message-ID: <1286@hao.UUCP>
Date: Sat, 1-Dec-84 18:33:20 EST
Article-I.D.: hao.1286
Posted: Sat Dec  1 18:33:20 1984
Date-Received: Tue, 4-Dec-84 05:29:14 EST
Distribution: net
Organization: High Altitude Obs./NCAR, Boulder CO
Lines: 40

We are about to embark on a journey into the deepest jungles
of  Ethernet, and we have a few questions.  Hopefully the explorers
who have been there before us will provide us with the benefit
of  their knowlege. 


1. We have been told that it is "Better" to install a single
length of cable, rather than join several smaller lengths with
barrel connectors.  The benefits of using many smaller lengths
are obvious.  The dangers of doing so are not so obvious.  Why
is  it better to use a single cable, and what kinds of problems
will  we encounter if we use several smaller lengths? 


2. Has anybody tried to install "zero impedance bump" connectors?
 Is this something that might help?  If not, why not? 


 3. We will be joining together machines running Unix with  machines
 running VMS (and possibly machines running VM/CMS).  We  hope
 to have systems using Decnet co-existing on the same cable 
 as systems using TCP/IP.  Are these things feasable?  Are there
 traps lying in wait for us? 


 4. Does the bit error rate increase as the cable length  approaches
 the specification maximum?  Is there some problem  other than
 collision time that constrains the length? 

 5. Do repeaters work?  Are they available?  Do the board makers
 suppy them?  Are they expensive?

-- 
"The number of arguments is unimportant unless some of them are correct."

Michael Ward, NCAR/SCD
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