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From: johnl@iecc.cambridge.ma.us (John R. Levine)
Newsgroups: comp.dcom.telecom
Subject: Re: Question About "Point of Demarcation"
Message-ID: <14376@accuvax.nwu.edu>
Date: 5 Nov 90 20:11:29 GMT
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X-Telecom-Digest: Volume 10, Issue 793, Message 4 of 11


In article <13499@accuvax.nwu.edu> you write:

>The only feature I have in my wiring which could be called a "point of
>demarcation" is a small terminal block on the inside wall of my garage,
>covered by a neoprene boot which says "Bell System" on it.

That's it.  It's the lightning protector, provided to keep your phones
from exploding if there's a hit nearby.  Post-MFJ demarcation points
are a somewhat bigger box with both the protector and an RJ-11 plug
and socket, so in case of trouble you can unplug your inside wiring,
plug in a known good phone, and tell easily if the trouble's inside or
outside.

As far as I can tell, every phone installation in the country is
supposed to run through a protector, so it is a sensible demarc point.
(Yeah, large PBX installations have an RJ-21 block for the demarc
point, but we can hope that such PBXes have someone around who knows
what's going on.)

Regards,

John Levine, johnl@esegue.segue.boston.ma.us, {spdcc|ima|world}!esegue!johnl