Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!killer!vector!nobody From: johnl@ima.ISC.COM (John R. Levine) Newsgroups: comp.dcom.telecom Subject: Re: AT&T letter to AT&T Cardholders on COCOTs (AOS) Message-ID: Date: 1 Sep 88 03:21:25 GMT Sender: chip@vector.UUCP Reply-To: harvard!ima!johnl@EDDIE.MIT.EDU (John R. Levine) Lines: 31 Approved: telecom-request@vector.uucp (USENET Telecom Moderator) X-TELECOM-Digest: volume 8, issue 138, message 1 X-Submissions-To: telecom@xx.lcs.mit.edu (Mailing List Coordinator) X-Administrivia-To: telecom-request@vector.uucp (USENET Telecom Moderator) In article dritchey@ihlpb.att.com writes: >> Why does AT&T manufacture COCOTS that don't let the customer choose >> an AT&T Card call by dialing 10288 directly? ... > >Almost universally, number screening and the like is handled by a LD >carrier in the nearest switching office. (I see no reason that an AOS >need be any different.) The phone itself would very likely have >absolutely nothing whatsoever to do with blocking access to 10XXX >numbers. (Most phones aren't that smart.) COCOTs are. They are designed to be attached to regular phone lines but to hijack all of your toll calls to the AOS provider that serves the COCOT. The local telco has not particular fondtness for COCOTs and provides no special services for them other than perhaps to block incoming collect calls. The COCOT typically buffers up the number you dial and then prefixes it by a long string of digits that calls the AOS and passes it the number you want. COCOTs probably make most of their money from the AOS charging you $3.00 for a call that would normally cost 60 cents, so they have a vested interest in making it as hard as possible to bypass the AOS. On a somewhat different note, I notice that I can now stick a regular credit card in an AT&T card caller phone (a coinless phone that makes it hard to call LD companies other than AT&T but you do get regular AT&T rates) and it changes the call to that credit card. It sounds like it passes the card number as DTMF digits more or less the same way it passes the calling card number if you use an AT&T card. Is it possible to dial the digits yourself and charge calls from regular phones to your (e.g.) Visa card? -- John R. Levine, IECC, PO Box 349, Cambridge MA 02238-0349, +1 617 492 3869 { ihnp4 | decvax | cbosgd | harvard | yale }!ima!johnl, Levine@YALE.something Rome fell, Babylon fell, Scarsdale will have its turn. -G. B. Shaw