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From: eric@lcc.la.Locus.COM (Eric Peterson)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Thinwire vs. Thickwire
Message-ID: <68@lcc.la.Locus.COM>
Date: 2 Oct 89 16:53:37 GMT
References: <8909291306.AA06775@jvnca.csc.org>
Reply-To: eric@elrond.la.locus.com (Eric Peterson)
Organization: Locus Computing Corp., Los Angeles
Lines: 53

In article <8909291306.AA06775@jvnca.csc.org> aggarwal@JVNCA.CSC.ORG (Vikas Aggarwal none) writes:
>
>Just to collect one's views on Thinwire ethernet vs Thickwire ethernet,
>I am listing what I know about the topic:
>
>THINWIRE
>
>	Flexible, Low cost ( app. $3.00 per meter ), 10 Mb bandwidth,
> 	Max segment length - 185 meters (30 nodes per segment), One 
>	multiport repeater can handle upto 8 segments

	From past experience, I recommend this for only very small or 
	temporary nets.  The cable is fragile, and the cable -> BNC
	connection is especially susceptible to breakage (we once had
	a janitor vacuuming the floor accidentally hit the cable and 
	yank it out of the BNC connector, he noticed the damage and
	managed to push the cable back into the connector - needless
	to say, it was a poor connection and that whole floor of the
	building suffered from intermittent Ethernet problems for 
	several days while we looked for the problem).

>THICKWIRE
>
>	More resilient for running through floors and ceilings,	Higher 
>	cost (app $11.00 per meter), 10 Mb bandwidth, Max segment 
>	length - 500 meters
>
>Based on the above, I would choose thickwire ONLY if the length of the
>segment had to be more than 500 mts or if the wire was going to run 
>through adverse areas.

	I feel that any area with users in it is "adverse."

>Any comments ??
>-vikas

	Another solution is to use multiport transceivers to disribute
	the Ethernet.  It is much less susceptible to damage (or I should
	say, if damage _does_ occur, it doesn't propagate throughout the
	network.)  I believe the spec allows xcvr cable runs up to 50
	meters away, and the multiports that I've seen allow up to two 
	levels of stacking the xcvrs.  Another advantage is that some
	Ethernet boards do not have the built-in thin wire BNC connector.

	A disadvantage is that manufacturers haven't seem to 
	standardize on their method of attaching the 15 pin connector
	(mechanically) to the board (grrrr).

Eric
-- 
Eric Peterson,	Locus Computing Corporation
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