Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!netsys!vector!telecom-gateway From: westmark!dave@rutgers.edu (Dave Levenson) Newsgroups: comp.dcom.telecom Subject: Re: While Phone Rings, Charges May Begin Message-ID: Date: 13 Jul 89 04:15:17 GMT Sender: news@vector.Dallas.TX.US Organization: Westmark, Inc., Warren, NJ, USA Lines: 58 Approved: telecom-request@vector.dallas.tx.us X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@vector.dallas.tx.us X-TELECOM-Digest: volume 9, issue 235, message 4 of 6 In article , zygot!john@apple.com (John Higdon) writes: > In article , lim@csvax.caltech.edu > (Kian-Tat Lim) writes: > > [From the LA Times "Consumer Views" column, by Don G. Campbell, 7/7/89. > > Paraphrased except for items in quotes.] > > QUESTION: J. T. observes several one-minute call charges on his/her MCI > > phone bill. These were made to answering machines that answer on the fifth > > ring; he/she always hung up after the third or fourth ring. > > ANSWER: [Complete and utter nonsense about clicks and machines making > > connections before ringing stops and such.] > When you place any call, local or long distance, upon connection of the > call you hear "ringback tone". This tone is supplied by the central > office at the called end and tells you that your call was successful > and that the party's phone is ringing (as opposed to not going through > or busy). > When the called party answers, ringback tone ceases immediately and the > connection "supervises", or in older parlance, "reverses". For the > majority of carriers that handle supervision, this is when the clock > starts. It makes no difference whether a machine answers or a person > answers, one thing is certain: ringback tone ending and supervision > beginning are a simultaneous event. If the machine answers on the fifth > ring, that's when billing begins and not before. There is an exception to this. If the called number is not a POTS (plain old telephone service) subscriber but an extension of a PBX (private branch exchange) that is reached by DID (direct inward dialing) trunks, then the audible ring signal is not generated by the far-end central office, but by the far-end PBX. Most PBX equipment acts like a central office in this case; it does not return answer supervision (start charging the caller) until the called end answers, and it stops the ring tone at the same time. Some PBX equipment also contains ACD (automatic call distribution) equipment. This usually answers immediately, and then plays a recording telling you that you are in a queue, until an agent is available. If no recording is provided, most ACD equipment will generate ring tones, even though the call has been answered. The AT&T System 85 PBX, when equipped with AUDIX (a voice-mail and call-coverage system that functions like a multi-user answering machine) will provide off-hook supervision at the time a call is sent to AUDIX for coverage (typically after three rings, if the station still hasn't answered). AUDIX will then generate ring tone until it is able to play the called party's personal greeting. This may mean that charging begins while ringing is still audible. -- Dave Levenson Voice: (201) 647 0900 Westmark, Inc. Internet: dave@westmark.uu.net Warren, NJ, USA UUCP: {uunet | rutgers | att}!westmark!dave [The Man in the Mooney] AT&T Mail: !westmark!dave