Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!spool.mu.edu!agate!telecom-request From: macy@fmsys.uucp (Macy Hallock) Newsgroups: comp.dcom.telecom Subject: Re: Modification of Ringback Tone by Subscriber Apparatus Message-ID: Date: 9 Jun 91 01:24:00 GMT Sender: Telecom@eecs.nwu.edu Organization: Hallock Engineering and Sales Medina, Ohio USA +1 216 722 3053 Lines: 33 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 11, Issue 444, Message 3 of 10 In article is written: >>> Were you calling a commercial establishment? A college dorm or >>> campus? Some other place where you were dialing directly to an >>> extension of a large private network? >> To answer your question: I heard the double-ring when calling the >> "Management Services" department at Toronto City Hall. > The double ring will indicate that the destination has answered your > call on its own equipment. The real implication of this is that you > are now being billed for the time that you are listening to ringing. What? This sounds incorrect to me. My 20+ years (am I _that_ old?) tells me that: DID trunks provide answer supervision to the telco office. That means billing does not occur until answer supervision is provided to the telco by the PBX. All PBX software I have seen for DID trunks works just this way: no supervision until a call is terminated/answered at a station. Rings and busies (and usually recorded intercepts) do not give answer supervision. Just like The Phone Company (tm) ... and this is done to their specification, too. And the FCC and CRTC agree, too. Perhaps you are thinking of some pager terminals or old style IMTS/MTS equipment that used DID trunks in a different way. Macy M. Hallock, Jr. N8OBG 216-725-4764 Home macy@fmsystm.UUCP macy@NCoast.ORG Note: macy@ncoast.org is best reply path to me. uunet!aablue!fmsystm!macy [No disclaimer, but I have no real idea what I'm saying or why I'm telling you]