Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!crdgw1!uunet!hayes!msieweke
From: msieweke@hayes.uucp
Newsgroups: comp.dcom.lans
Subject: Re: 10Base-T hubs
Message-ID: <3901.27f9e38a@hayes.uucp>
Date: 3 Apr 91 14:15:38 GMT
References: <1991Apr03.004515.12021@rs6000.cmp.ilstu.edu>
Distribution: usa
Organization: Hayes Microcomputer Products, Norcross, GA
Lines: 51

In article <1991Apr03.004515.12021@rs6000.cmp.ilstu.edu>, ejbehr@rs6000.cmp.ilstu.edu (Eric Behr) writes:
> We're considering using our twisted pair wires for Ethernet. Hence tons of
> questions, some of which are below:
> 
> - aside from distance/no. of stations differences, is UTP inherenly less
> reliable than thin/thick E-net?

What is reliable?  Our most frequent problem with our thinwire segments is
people disconnecting their equipment and not putting back the jumper.  This
brings down the net for everyone on the same cable.  Our thickwire xceiver
cables frequently come out of the back of the equipment.  So far (5 months)
we have had no problems with our UTP segments.  If someone screws up his/her
machine, no one else is affected.  Also, with Synoptics equipment our UTP
traffic is easier to manage.

> - in a smallish network (30 nodes, less that 300 ft.) is a passive hub OK?
> Price difference between active and passive hubs is substantial...

I don't know the difference.  I have seen TP hubs for about $150 per port.
Is there another type besides this?

> - (must be obvious...) does 10Base-T *have* to use star topology?
> If so, then (troubleshooting aspects set aside) I save maybe $500 in
> thinwire cabling costs but I lose $1000+ on a hub... I think that
> 10Base-T's economic advantages are a bit overblown given the current
> prices; am I right?

> Eric Behr, Illinois State University, Mathematics Department
> Internet: ejbehr@rs6000.cmp.ilstu.edu    Bitnet: ebehr@ilstu

Yes, 10BaseT is always physically a star.  Its advantage is that
you can run it off of existing wiring (if it meets spec).  You save
the cost of running new wire (very expensive if contracted out).

You brush off the troubleshooting aspects as though they weren't a
consideration.  How much is your time worth?  10BaseT eliminates several
potential problems and will save you time every month that you use it.
It's the gift that keeps on giving.  :-)

In my experience only the people in a government or university are short-
sighted enough to ignore the time savings.  This is not intended as an
insult.  I worked for Georgia Tech for 7 years, and every purchase had 
to be justified on tangible cost.  No one took the time to investigate
the _people_ costs of any purchase decision.  Usually quality wasn't an 
obvious factor in the decision either.

I hope this helps.
-- 
Mike Sieweke                            ...!uunet!hayes!msieweke
Hayes Microcomputer Products            msieweke@hayes.uucp
Norcross, Georgia                       hayes!msieweke@uunet.uu.net