Method and apparatus for preventing wireless fraud

• US 5,541,977 A
• Filed: 05/12/1995
• Issued: 07/30/1996
• Est. Priority Date: 03/11/1993
• Status: Expired due to Term

• Current Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Rubenstein, Zev C., Hodges, Steven J.
• Primary Examiner(s): Bost, Dwayne D.
• Application Number:
  US08/440,183
• Time in Patent Office: 445 Days
• Field of Search: 379/58, 379/59, 379/62, 340/825.3, 340/825.34, 340/825.5, 380/23
• US Class Current: 455/411
• CPC Class Codes: H04W 12/06 Authentication
• CPC Class Codes: H04W 12/126 Anti-theft arrangements, e.g. protection against subscriber identity module [SIM] cloning
• CPC Class Codes: H04W 12/71 Hardware identity

Abstract

The use of stolen mobile identification number (MIN) and electronic serial number (ESN) information to fraudulently place wireless calls is prevented by having the switches of multiple wireless carriers forward or direct, over a telephone connection, all calls placed from selected MINs to a central authentication platform that serves the multiple wireless carriers. The central authentication platform engages in a so-called "challenge-response" authentication with local processors that are interfaced to the wireless telephones from which non-fraudulent calls originate. The challenge-response authentication uses a shared secret key (S-Key) that is not broadcast over the interface, thus preventing the key from being "stolen". A call from a wireless telephone that is not interfaced to a local processor capable of successfully completing the challenge-response authentication is blocked, while a call from a wireless telephone having a local processor capable of successfully completing the challenge-response authentication is completed to the number desired by the customer. Advantageously, since the central authentication platform serves multiple wireless carriers, the need for one wireless carrier to access the database of another is alleviated and the expense of providing additional security is reduced.

Claims

1. A method for use in completing calls from first and second wireless telephones each having a MIN, said wireless telephones being served by respective first and second wireless carriers, the method comprising the steps of:

receiving at first and second mobile switching centers belonging, respectively, to said first and second wireless carriers, requests for completion of a wireless call from each of said wireless telephones;

establishing with an authentication platform, from each of said first and second mobile switching centers, respective first and second voice channel telephone connections, said authentication platform serving said first and second wireless carriers, if said first and second requests originated from wireless telephones belonging to a group of predetermined MINs;

supplying to said authentication platform said MINs of said first and second wireless telephones, said MIN of said first wireless telephone being supplied over said first telephone connection and said MIN of said second wireless telephone being supplied over said second telephone connection;

transmitting respective challenges from said authentication platform to each of said first and second wireless telephones, via said first and second telephone connections and said first and second mobile switching centers of said first and second wireless carriers, each of said challenges being developed by said authentication platform from respective secret keys stored therein in association with said respective MINs of said first and second wireless telephones; and

denying, by said authentication platform, said first or said second call requests for which a proper response to its respective challenge is not received.

2. A method for use in completing calls from wireless telephones, each wireless telephone being served by one of a plurality of wireless carriers, the method comprising the steps of:

receiving requests at mobile switching centers of said plurality of wireless carriers for completion of calls from said wireless telephones;

forwarding over voice paths, from said mobile switching centers to an authentication platform serving said plurality of wireless carriers, those of said calls originated from wireless telephones having MINs that belong to a particular predefined group of MINs;

transmitting a challenge from said authentication platform to each of said wireless telephones via, said mobile switching centers of said plurality of wireless carriers; and

blocking those of said calls for which a proper response to said challenge is not received.

3. The invention as defined in claim 2 wherein responses to said challenges are supplied by local processors connected to said wireless telephones.

4. The invention as defined in claim 3 wherein said local processors are external to said wireless telephones.

5. The invention as defined in claim 2 wherein said challenges are transmitted over voice path connections between said wireless telephones and said authentication platform.

6. The invention as defined in claim 2 wherein at least one of said particular predefined group of MINs is a non-dialable MIN.

7. The invention as defined in claim 2 wherein, in said forwarding step, said calls are forwarded by said mobile switching centers to said authentication platform by being routed to a particular telephone number.

8. The invention as defined in claim 7 wherein said particular telephone number is one that requires translation for said routing to successfully complete.

9. The invention as defined in claim 2 wherein, for at least one of said calls, a proper response to said challenge is received and further including the steps of:

blocking said at least one call if information stored in said authentication platform for said MIN for said at least one call indicates that said at least one call is not to be completed.

10. The invention as defined in claim 2 further including the steps of:

receiving at said authentication platform responses to said challenges;

receiving at said authentication platform telephone numbers to which said calls are to be completed; and

completing said calls for which said received responses are proper responses to said respective ones of said telephone numbers received for said calls.

11. The invention as defined in claim 10 further including the step of:

responsive to receipt of said responses, transmitting prompts requesting said telephone numbers to which said calls are to be completed.

12. An authentication platform for use in routing calls from wireless telephones, comprising:

means for receiving a request from one of a plurality of wireless carriers for completion of a call from a wireless telephone having a particular MIN, said request including said particular MIN and having been forwarded to said authentication platform over a voice path by said one of said plurality of wireless carriers because said particular MIN belongs to a predefined group of MINs;

means responsive to said particular MIN for generating and transmitting a challenge to said wireless telephone via said one of said plurality of wireless carriers;

means for determining a correct response to said challenge;

means for receiving a response to said challenge; and

means for blocking said call if a response to said challenge matching said correct response is not received.

13. The invention as defined in claim 12 wherein said means for generating and transmitting generates said challenge using a secret key that (i) is unique to said particular MIN and (ii) is not transmitted by said means for generating and transmitting.

14. The invention as defined in claim 12 wherein said means for receiving receives said response from a voice path connection between said wireless telephone and said authentication platform.

15. The invention as defined in claim 12 wherein said means for generating and transmitting transmits said challenge over a voice path connection between said wireless telephone and said authentication platform.