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From: "Fred R. Goldstein" <>
Subject: Re: Answer Supervision on PBX
Date: 22 Oct 90 16:31:13 GMT
Organization: Digital Equipment Corp., Littleton MA USA

In article <>, (Dave Michaels
cccc) writes...

>We have an AT&T Definity something orother PBX here on campus.  I
>recently discovered that the CO does not send answer supervision info
>to the PBX. As a result, we pay for calls that ring for more than 30
>seconds if they are answered or not.  Any PBX's not have this problem?
>Why won't (cant?) NJ Bell provide that information to the PBX?  Also,
>is there any way around the fact that since the school is a 'business'
>with a 'business line' the residents of the residence halls who are on
>the system must pay for local calls?

>Do all schools with PBX's have these problems?
>[Moderator's Note: Not all schools have that problem. Just the ones
>which buy cheap equipment thinking they will save money.   PAT]

No fair, Pat.  It's NOT the fault of the PBX!

Central offices routinely deny answer supervision to subscribers.
It's not impossible for them to provide it, but as a rule, telcos
consider answer supervision a private matter. (ISDN, on the other
hand, normally provides it, but sometimes will fail when the other end
is analog.)

If NJBell wanted to be nice about it, they'd provide answer
supervision, but I haven't met a Bell yet who was routinely nice about
it.  Maybe they think it's a benefit of Centrex service, since that
does provide accurate billing on message toll calls. (It doesn't pass
supervision; it is CO-based, so the CO uses its own knowledge in
writing up the bills.)  So PBX users suffer.  Maybe the FCC will
eventually end this little scam but it has lasted so far.  

Fred R. Goldstein 
Digital Equipment Corp., Littleton MA voice: +1 508 486 7388

Do you think anyone else on the planet would share my opinions, let
alone a multi-billion dollar corporation?

Date: Tue, 8 Sep 92 23:20 PDT
From: (John Higdon)
Organization: Green Hills and Cows
Subject: Re: New Phone Number Intercept

On Sep 7 at 22:24, TELECOM Moderator writes:

> Speaking of live operator intercepts, are there still any of those
> situations where the operator responds but cannot hear the caller
> because the LD carrier does not open the mouthpiece until the call has
> supervised, which it will never do with an operator?

> Are all the OCC's opening the talk path now?   PAT]

It was AT&T that (exclusively?) participated in this practice, and it
began some years ago. It was put in place to prevent the practice of
"black boxing" and also to protect itself from itself. It seems that
many of the AT&T PBXes sold and installed by none other than AT&T had
misprogrammed DID circuits that never supervised. Any call made to
such lines was a "free" call.

And we are not talking about just a few systems. This mishandling was
rampant. AT&T was losing big bucks on long distance because of the
incompetence of its own installers and that of its contractors. Also,
there were a few unscrupulous customers who intentionally programmed
DID circuits to never supervise. The fix was to not enable caller to
callee audio until the circuit was supervised. This way the caller
could hear call progress tones, but no two-way communication could
take place.

A complaint from a customer describing this condition would result in
the dispatch of service personnel to reprogram the System 75, 85, or

To my knowledge, the OCCs never bothered with this practice. And I
believe AT&T is still doing it.

        John Higdon         |   P. O. Box 7648   |   +1 408 264 4115      | San Jose, CA 95150 |       M o o !

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