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From: dave@westmark.westmark.com (Dave Levenson)
Newsgroups: comp.dcom.telecom
Subject: Re: Answer Supervision From Loop Start Circuits
Message-ID: <16797@accuvax.nwu.edu>
Date: 11 Feb 91 03:29:16 GMT
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X-Telecom-Digest: Volume 11, Issue 111, Message 2 of 12


In article <74365@bu.edu.bu.edu>, csense!bote@uunet.uu.net (John
Boteler) writes:

> Tom Lowe describes a costly and painful procedure for extracting
> answer supervision from NJ Bell.

 ...

> Solution: order CENTREX. That's it! No special tariffs, no unnecessary
> pain (other than the usual CENTREX programming screw-ups), and you get
> features as part of the deal. The answer supervision is provided as an
> OSI (Open Switch Interval) at least on 3*Way calls, and possibly on
> single outbound calls when served by a #1ESS. #5s and their ilk are
> another question.

I would like to know what sort of central office John is talking
about.  Here in NJ, I have seen Centrex provided by 5 crossbar, 1ESS,
1AESS, and 5ESS.  None of those switches routinely provide answer
supervision to centrex subscriber lines.

What all of these switches do provide is an open circuit interval (500
msec for ESS, ~100 msec for 5 crossbar) when the far end party
disconnects.  This is not supervision.  This indicates an abandoned
call, and is provided to the remaining party after the other party has
disconnected, on both originating and terminating calls.

Answer supervision, which indicates when the called party has
answered, is provided under tarriff, and usually consists of a battery
reversal toward the calling party when the called party answers.


Dave Levenson		Internet: dave@westmark.com
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