Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!lll-tis!ames!pasteur!ucbvax!think.UUCP!johnl
From: johnl@think.UUCP (John R. Levine)
Newsgroups: comp.dcom.telecom
Subject: Re: Calling card numbers
Message-ID: <8802232059.AA14028@ima.ISC.COM>
Date: 23 Feb 88 20:59:39 GMT
References: <8802230101.AA05346@ucbvax.Berkeley.EDU>
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: ima!johnl (John R. Levine)
Organization: Not enough to make any difference
Lines: 26
Approved: telecom@xx.lcs.mit.edu

In article <8802230101.AA05346@ucbvax.Berkeley.EDU> Patrick_A_Townson@cup.portal.COM writes:
>Very curiously, I happen to have an Illinois Bell Calling Card, an AT&T
>Calling Card and an MCI Credit Card. The first two have the identical
>data on them including the PIN. The MCI card differs only in one respect;
>the PIN is different (by a couple digits!). Apparently AT&T assigns all the
>PIN's and other details on these, regardless of which OCC (or themself) has
>the account.

No, actually the local operating company assigns your calling card number, and
provides it to AT&T. (This info from my cousin who runs a small telco in
Vermont and finds making up the calling card numbers to be a minor pain. The
RBOCs provide the info directly, the small companies via a trade group that
maintains their data base.) It appears that the various OCCs invent card
numbers by themselves, using a scheme which resembles the original, i.e. your
10-digit phone number followed by 4 extra digits except when toll fraud is a
problem in which case they make up all 14 digits.

If the various long distance companies are really all equally at arms' length
from the local telcos, I see no reason why the OCCs couldn't get their calling
card numbers from the telcos, so that you would have one calling card number
that would work no matther what long distance company a phone exchange
happened to route your call to, making life much easier for us who use pay
phones in airports.
-- 
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