Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!netsys!vector!telecom-gateway From: DREUBEN@eagle.wesleyan.edu) (DOUGLAS SCOTT REUBEN) Newsgroups: comp.dcom.telecom Subject: Bypassing an AOS Message-ID: Date: 18 Jun 89 20:56:32 GMT Sender: news@vector.Dallas.TX.US Lines: 76 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 203, message 1 of 5 Hello! If anyone out there ever has had to use NTS (National Telephone Sys., I think) from a COCOT or hotel or for whatever reason and not been able to get a hold of an AT&T operator, there is a trick you can use, although it may not get you a human AT&T operator. From what I understand, all the LD services (AT&T, MCI, Sprint, etc.) and the AOS firms (ITI, NTS, etc.) are charged for accessing the national calling card database (or whatever the system is called) for verifying a calling card. AT&T is supposedly charged $.07 per call, while the AOS firms are charged something like $.40. This is one of the reasons they cite when they defend their higher rates. In any event, many AOS firms don't really check. ITI (International Telecharge) just checks to make sure the card "looks" valid, ie, a real area code, a real exchange in that area code, and a somewhat valid looking calling card PIN number. During busy hours, they are less careful, as I've entered "wrong" PINs and totally wrong numbers at times and it went through fine. Late at night they check more often, and frequently a false PIN that was accepted at 5PM won't work at 11PM the same evening. NTS, on the other hand, seems to be doing something that I, as an AT&T customer, find *very* disturbing. When I use an NTS payphone, I get the NTS "boing" tone to enter my calling card number. After that, NTS says "please wait for card verification". I hear lots of clicks, and after a minute or so, the call goes through, and you hear "Thank you for using NTS". Sounds normal, right? Fine, but enter an INVALID card number, and see what happens then. You go through the normal routine, ie, tone, then a long period of clicks, but rather than say "Invalid number" or whatever, you hear the *AT&T* system come on and say "Please dial your card number again now, the card number you have dialed in not valid". THEN, if you enter a VALID AT&T/Bell card number, you hear "Thank you for using AT&T"!!! It seems what NTS is doing is using AT&T's calling card system to verify calls for them, and then place the call over NTS after they use AT&T to check! Here's what I think happens: 1. Caller calls NTS with a 0+ call. 2. NTS gets the card number info, and then dials (via AT&T) 0+ac-dest number, waits for the AT&T tone, and then dials your card number. If the NTS system hears "Thank you for using AT&T" (or knows that a valid AT&T card gets a response faster than an invalid one), it hangs up, and places the call over NTS lines, so you don't get billed via AT&T. 3. If the call is invalid, it frequently leaves the line open so you can hear the invalid message from AT&T. You can THEN enter your real number, and get billed via AT&T (but the location may be different from where the payphone is physically located, as the NTS center is probably not near the payphone, and the call is sent out from the NTS center, not the payphone.) I've tried this a few times, and it always happens this way. I've also entered an invalid number, and then gotten the AT&T "please re-enter" recording, dialed in my AT&T card, and was later billed by AT&T with no mention of NTS. The call also came from Maryland, if I recall correctly, although I was in Springfield, Mass, calling to Boston. Has anyone had similar experiences with NTS? Is my supposition correct? Is NTS using AT&T to verify card calls, thus saving at least $.40 per call and running up AT&T's bill instead? Is this legal? Does AT&T know about this? Well, thought I'd pass the results of my experiences with NTS along and see what anyone can come up with... -Doug dreuben%eagle.weslyn@wesleyan.bitnet dreuben@eagle.wesleyan.edu (and just plain old "dreuben" to the few locals left...! :-) ) (about 5 now, right?)