Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!hplabs!hpfcso!hpcnd!jason@hpcndjdz.CND.HP.COM
From: jason@hpcndjdz.CND.HP.COM (Jason Zions)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: How is UTP fault-tolerant?
Message-ID: <810022@hpcndjdz.CND.HP.COM>
Date: 21 May 91 23:32:46 GMT
References: <1991May20.133442.1309@banana.fedex.com>
Organization: HP Colorado Networks Division
Lines: 16

UTP is fault-tolerant in the sense that a cut cable generally affects only
the single node attached to it; the UTP hub will detect that one of its
ports is busted in some sense and take it out of the loop. If everyone was
one a single stretch of coax, a cut cable would affect every node on that
segment. Breaking the coax to insert another tee would stop the entire
segment, while adding a new UTP line to a hub shouldn't affect any other
users.

Of course, you're still vulnerable on the 10Base2 or 10Base5 links between
the hubs, and if you've cascaded hubs via UTP you have a larger
vulnerability on the cascading UTP lines, but that's a lot more manageable
than barrel and tee connectors etc. Also, you have the added vulnerability
of an active device (the hub itself) which might fail and take out n devices
with it.

Jazz