Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!apple!netcom!cmilono
From: cmilono@netcom.COM (Carlo Milono)
Newsgroups: comp.dcom.lans
Subject: Re: LAn on 50-conductor
Message-ID: <1991Mar25.172813.3387@netcom.COM>
Date: 25 Mar 91 17:28:13 GMT
References: <1991Mar22.221831.17898@beach.csulb.edu>
Organization: Netcom - Somewhere in the S.F. Bay Area
Lines: 33

In article <1991Mar22.221831.17898@beach.csulb.edu> sichermn@beach.csulb.edu (Jeff Sicherman) writes:
>
>  Is it feasible to run a LAn sharing cabling in a 50-conductor telco-type
>cable that is currently being used with a 1A2 phone system. What speed
>limitations are there. ANy products more compatible with this than others ?
>Any suggestions, critiques, experiences, etc. would be appreciated.


10BASET allows for this with some caveats.  1A2 is an analog-based system
with A-leads and lamps, with the strongest circuits being the Tip and Ring
under ringing voltage.  Such systems run on 75-pair and 100-pair cables
as well (ye old call directors).

10BASET was set to allow for such cable runs and is quite immune to any
telephonic voltages, however, it is not wise to mix multiple LAN runs in
a single 25-pair cable run due to interference with one another, but a
single 10MBps works fine with 1A and 1A2 Key equipment, with a limit of
100 meters.

10BASET is 10BASET, but some vendor's products are a bit more susceptible
to external EMI/RFI than others, but the spec is a spec...some just exceed
it a bit.

HOWEVER: not all wire is created equal and some runs may have weird 
impedance characteristics - watch out for bridged cables (with bridge
clips), and CPC adapters (Cable-Phone-Cable) where multiple sets
share a single cable.
-- 
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|  Carlo Milono:  cmilono@netcom.apple.com   or   apple!netcom!cmilono     |
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