Method of pre-authorizing handovers among access routers in communication networks

• US 7,684,798 B2
• Filed: 11/09/2001
• Issued: 03/23/2010
• Est. Priority Date: 11/09/2001
• Status: Expired due to Fees

• Current Assignee: RPX Corporation
• Original Assignee: Nokia Corporation
• Inventors: Sengodan, Senthil, Gopal, Ram, Krishnamurthi, Govind
• Primary Examiner(s): Appiah; Charles N
• Assistant Examiner(s): Peaches; Randy
• Application Number:
  US09/986,778
• Publication Number:
  US 20030092444A1
• Time in Patent Office: 3,056 Days
• Field of Search: 455/456.2, 455/67.11, 455/67.14, 455423-425, 455/453, 455/442, 455/436, 455/435.1, 455/422.1, 455/428, 455/439, 455/552.1, 455/555, 455/554.1, 455/462, 455/438
• US Class Current: 455/436
• CPC Class Codes: H04W 12/08 Access security
• CPC Class Codes: H04W 36/0016 Hand-off preparation specially adapted for end-to-end data sessions
• CPC Class Codes: H04W 88/005 Data network PoA devices

Abstract

An apparatus and method is provided for facilitating the handoff of a mobile terminal from a first access device in a first network to a second access device in a second network. Prior to performing a handoff operation, the first access device inquires as to whether the mobile terminal is authorized to be handed off to the second access device and, in response thereto, completes the handoff. If the mobile terminal is not authorized to be handed off to the second access device, the handoff operation is inhibited, preferably without using any radio frequency resources of the second access device.

Claims

1. A method comprising:

receiving from a first access router in a first network by a second access router in a second network that serves a different service area a request for authorization inquiry including an identifier that identifies a mobile terminal that is a candidate for a handoff operation;

causing a database to be queried via a server to determine whether the second access router is authorized to accept a handoff operation for the mobile terminal;

in response to determining that the mobile terminal is authorized to be handed off to the second access router, performing a handoff operation from the first access router to the second access router; and

in response to determining that the mobile terminal is not authorized to be handed off to the second access router, inhibiting the handoff operation from the first access router to the second access router.

2. The method of claim 1, wherein performing a handoff operation comprises transferring context information from the first access router to the second access router.

3. The method of claim 1, wherein the method is performed without allocating any radio frequency resources of the second access router to communicate with the mobile terminal until after it is determined that the mobile terminal is authorized to be handed off to the second access router.

4. The method of claim 1, wherein the causing the database to be queried comprises causing the database to be queried on the basis of a list of access routers that are authorized to accept handoffs from the mobile terminal.

5. The method of claim 1, wherein the causing the database to be queried comprises causing the database to be queried to determine authorization based on a time of day.

6. The method of claim 1, wherein the causing the database to be queried comprises causing the database to be queried on the basis of dynamic loading conditions.

7. The method of claim 1, further comprising modifying the database on the basis of dynamic loading conditions, such that authorization is dependent upon dynamic loading conditions.

8. The method of claim 1, wherein the method is conducted between access routers that use same access technology.

9. The method of claim 1, wherein the method is conducted between access routers that use heterogeneous access technologies.

10. The method of claim 1, wherein querying the database is performed using the DIAMETER protocol.

11. The method of claim 1, wherein querying the database is performed using the Session Initiation Protocol (SIP) protocol.

12. The method of claim 1, comprising sending a request for authorization information concerning the mobile terminal to an administrative server associated with a network served by the second access router, the administrative server comprising an authentication, authorization and accounting (AAA) server.

13. The method of claim 1, comprising sending a request for authorization information concerning the mobile terminal to an administrative server associated with a network served by the second access router, the administrative server comprising a Session Initiation Protocol (SIP) server.

14. The method of claim 1 comprising querying the database on the basis of a membership plan associated with a subscriber of the mobile terminal.

15. An access router comprising:

a processor, and memory storing computer executable instructions that, when executed by the processor perform;

receiving by the access router in a network from another access router in another network that serves a different service area a request for an authorization inquiry including an identifier that identifies a mobile terminal that is a candidate for a handoff operation;

causing a database to be queried via a server to determine whether the access router is authorized to accept a handoff operation for the mobile terminal;

in response to determining that the mobile terminal is authorized to be handed off to the access router, performing a handoff operation with the another access router; and

in response to determining that the mobile terminal is not authorized to be handed off to the access router, inhibiting the handoff operation with the another access router.

16. The access router of claim 15, wherein performing a handoff operation comprises transferring context information from the another access router to the access router.

17. The access router of claim 15, wherein the method is performed without allocating any radio frequency resources of the access router to communicate with the mobile terminal until after it is determined that the mobile terminal is authorized to be handed off to the access router.

18. The access router of claim 15, wherein the computer executable instructions, when executed, performs causing the database to be queried on the basis of a list of access routers that are authorized to accept handoffs of the mobile terminal.

19. The access router of claim 15, wherein the computer executable instructions, when executed, performs causing the database to be queried to determine authorization that is dependent on a time of day.

20. The access router of claim 15, wherein the computer executable instructions, when executed, performs causing the database to be queried on the basis of dynamic loading conditions.

21. The access router of claim 15, wherein the computer executable instructions, when executed, performs causing information concerning current loading conditions to be provided to the database, such that authorization is dependent upon dynamic loading conditions.

22. The access router of claim 15, wherein the access router serves mobile terminals using Internet Protocol.

23. The access router of claim 15, wherein the access router uses a different access technology than the another access router from which the candidate handoff is to be performed.

24. The access router of claim 23, wherein the access router uses wireless LAN technology, and wherein the another access router uses GPRS technology.

25. The access router of claim 15, wherein the access router uses the same access technology as the another access router from which the candidate handoff is to be performed.

26. The access router of claim 15, wherein the computer executable instructions, when executed, performs sending the authorization information to an administrative server using DIAMETER protocol.

27. The access router of claim 15, wherein the computer executable instructions, when executed, performs sending the authorization information to an administrative server using Session Initiation Protocol (SIP) protocol.

28. The access router of claim 15, wherein the computer executable instructions, when executed, performs causing the database to be queried on the basis of a membership plan associate with a subscriber of the mobile terminal.

29. A method comprising:

prior to initiating a handoff operation of a mobile terminal from a first network served by a first access router to a second network served by a second access router, sending an authorization inquiry from the first access router to a home network associated with the mobile terminal via a server, the authorization inquiry including an identifier that identifies the mobile terminal;

receiving a result of a database query from the home network, wherein the result of the database query indicates whether the mobile terminal is authorized to be handed off to the second access router;

in response to determining that the mobile terminal is authorized to be handed off to the second access router, performing a handoff operation from the first access router to the second access router; and

in response to determining that the mobile terminal is not authorized to be handed off to the second access router, inhibiting the handoff operation from the first access device to the second access router.

30. The method of claim 29, wherein receiving the result of the database query from the home network comprises receiving a result that depends on dynamic loading conditions associated with the second access router.

31. The method of claim 29, wherein receiving the result of the database query from the home network comprises receiving a result corresponding to querying the database to determine authorization based on a time of day.

32. The method of claim 29, wherein receiving the result of the database query from the home network comprises receiving a result corresponding to querying the database on the basis of dynamic loading conditions.

33. The method of claim 29, wherein the method is performed without allocating any radio frequency resources for communicating between the second access router and the mobile terminal until after it has been determined that the mobile terminal is authorized to be handed off to the second access router.

34. The method of claim 29, comprising sending a request for authorization information concerning the mobile terminal to an administrative server associated with the second network, the administrative server comprising an authentication, authorization and accounting (AAA) server.

35. The method of claim 29, comprising sending a request for authorization information concerning the mobile terminal to an administrative server associated with the second network, the administrative server comprising a Session Initiation Protocol (SIP) server.

36. The method of claim 29 comprising querying the database on the basis of a membership plan associated with a subscriber of the mobile terminal.