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From: ben@hpcvlx.cv.hp.com (Benjamin Ellsworth)
Newsgroups: comp.dcom.telecom
Subject: Re: Leaving Brief Messages With Free Collect Calls
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Date: 10 Sep 90 22:52:42 GMT
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X-Telecom-Digest: Volume 10, Issue 635, Message 5 of 13


> I have had occasions where people who called me have asked me,
> surprised, "How come you answered even before the phone rang at all?"
> when I had distinctly heard the phone ring twice at my end.

> Any switch gurus care to shed any light on this?

I am not a switch guru, but a professor of mine (Dr. Burton at BYU)
was an ex-Bell Labs man, and he mentioned in passing that some work
had gone into the long distance switching network to temporally
displace the ring that the caller heard from the ring signal that the
callee heard.  This was done specifically to disrupt the "if it rings
twice, call me" type of signalling.


Benjamin Ellsworth                                     ben@cv.hp.com
                     All relevant disclaimers apply.