Soft handoff across different networks assisted by an end-to-end application protocol

• US 20040199637A1
• Filed: 02/12/2003
• Published: 10/07/2004
• Est. Priority Date: 02/12/2003
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Li, Peng, Mahendran, Arungundram C.
• Granted Patent: US 8,037,188 B2
• Time in Patent Office: Days
• US Class Current: 709/227
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection

Abstract

A method for soft handoff across different networks is disclosed. A first communication link through a first network is used for communicating between a first user agent and a second user agent. The user agents negotiate to use a second communication link for the same call. The second communication link is established through a second network between the first user agent and the second user agent while maintaining the first communication link. Related data is sent through the first communication link and the second communication link such that the related data is for the same call. The first communication link is dropped and communication is continued using the second communication link.

Claims

1. A method for soft handoff across different networks, the method comprising:

communicating between a first user agent and a second user agent using a first communication link through a first network;

negotiating to use a second communication link for the same call;

establishing the second communication link through a second network between the first user agent and the second user agent while maintaining the first communication link;

sending related data through the first communication link and the second communication link such that the related data is for the same call;

dropping the first communication link; and

continuing communication using the second communication link.

2. The method as defined in claim 1, wherein the first user agent comprises an application and wherein the application performed the establishing of the second communication link and the sending of the related data.

3. The method as defined in claim 1, wherein the related data has the same data format.

4. The method as defined in claim 1, wherein the related data has different data formats.

5. The method as defined in claim 1, wherein the related data is voice data.

6. The method as defined in claim 1, wherein the related data is multimedia data.

7. The method as defined in claim 1, wherein the related data comprises signaling information for the same call.

8. The method as defined in claim 1, wherein the second user agent is receiving the related data from the first communication link and the second communication link, and wherein the second user agent uses the related data from only one of the communication links.

9. The method as defined in claim 1, wherein the first network and the second network are each a network selected from the group consisting of a CDMA network, a Local Area Network (LAN), a wireless LAN, a global computer network, a General Packet Radio Service (GPRS) network, a Global System for Mobile Communication (GSM) network, a Universal Mobile Telecommunications System (UMTS) network, and the Public Switched Telephone Network (PSTN).

10. The method as defined in claim 1, further comprising discovering the second network before the second communication link is established.

11. The method as defined in claim 10, further comprising determining whether the second network should be used before the second communication link is established through use of network preference criteria.

12. The method as defined in claim 1, wherein the second user agent comprises a legacy user agent and wherein a network application gateway facilitates the soft handoff from the first network to the second network.

13. The method as defined in claim 1, wherein the negotiating is performed before the establishing of the second communication link.

14. The method as defined in claim 1, wherein the negotiating is performed during the establishing of the second communication link.

15. The method as defined in claim 1, wherein the negotiating is performed after the establishing of the second communication link.

16. A method for soft handoff across different networks, the method comprising:

communicating between a first user agent and a second user agent using a first communication link through a first network;

negotiating to use a second communication link for the same call;

establishing the second communication link through a second network between a third user agent and the second user agent while maintaining the first communication link;

sending related data through the first communication link and the second communication link such that the related data is for the same call;

dropping the first communication link; and

continuing communication using the second communication link between the third user agent and the second user agent.

17. A user agent for soft handoff across different networks, the user agent comprising:

a processor;

memory in electronic communication with the processor; and

an application stored in the memory, the application being configured to implement a method comprising;

communicating with a second user agent using a first communication link through a first network;

negotiating to use a second communication link;

establishing the second communication link through a second network with the second user agent while maintaining the first communication link;

sending related data through the first communication link and the second communication link such that the related data is for the same call;

dropping the first communication link; and

continuing communication using the second communication link.

18. The user agent as defined in claim 17, wherein the related data has the same data format.

19. The user agent as defined in claim 17, wherein the related data has different data formats.

20. The user agent as defined in claim 17, wherein the related data is voice data.

21. The user agent as defined in claim 17, wherein the related data is multimedia data.

22. The user agent as defined in claim 17, wherein the related data comprises signaling information for the same call.

23. The user agent as defined in claim 17, wherein the first network and the second network are each a network selected from the group consisting of a CDMA network, a Local Area Network (LAN), a wireless LAN, a global computer network, a General Packet Radio Service (GPRS) network, a Global System for Mobile Communication (GSM) network, a Universal Mobile Telecommunications System (UMTS) network, and the Public Switched Telephone Network (PSTN).

24. The user agent as defined in claim 17, wherein the method implemented by the application further comprises discovering the second network before the second communication link is established.

25. The user agent as defined in claim 24, wherein the method implemented by the application further comprises determining whether the second network should be used before the second communication link is established through use of network preference criteria.

26. The user agent as defined in claim 17, wherein the second user agent comprises a legacy user agent and wherein the method implemented by the application further comprises communicating with a network application gateway that facilitates the soft handoff from the first network to the second network.

27. The user agent as defined in claim 17, wherein the method implemented by the application performs the negotiating before the establishing of the second communication link.

28. The user agent as defined in claim 17, wherein the method implemented by the application performs the negotiating during the establishing of the second communication link.

29. The user agent as defined in claim 17, wherein the method implemented by the application performs the negotiating after the establishing of the second communication link.

30. A network application gateway for soft handoff across different networks, the network application gateway comprising:

a processor;

memory in electronic communication with the processor; and

an application stored in the memory, the application being configured to implement a method comprising;

enabling communications between a first user agent and a legacy user agent using a first communication link through a first network;

negotiating to use a second communication link;

establishing the second communication link through a second network with the first user agent while maintaining the first communication link;

sending related data through the first communication link and the second communication link such that the related data is for the same call, while maintaining one communication link with the legacy user agent;

dropping the first communication link; and

continuing communication using the second communication link.

31. A computer-readable medium for storing program data, wherein the program data comprises executable instructions for implementing a method in a communication device, the method comprising:

communicating between a first user agent and a second user agent using a first communication link through a first network;

negotiating to use a second communication link for the same call;

establishing the second communication link through a second network between the first user agent and the second user agent while maintaining the first communication link;

sending related data through the first communication link and the second communication link such that the related data is for the same call;

dropping the first communication link; and

continuing communication using the second communication link.

32. The computer-readable medium as defined in claim 31, wherein the related data has the same data format.

33. The computer-readable medium as defined in claim 31, wherein the related data has different data formats.

34. The computer-readable medium as defined in claim 31, wherein the related data is voice data.

35. The computer-readable medium as defined in claim 31, wherein the related data is multimedia data.

36. The computer-readable medium as defined in claim 31, wherein the related data comprises signaling information for the same call.

37. The computer-readable medium as defined in claim 31, wherein the second user agent is receiving the related data from the first communication link and the second communication link, and wherein the second user agent uses the related data from only one of the communication links.

38. The computer-readable medium as defined in claim 31, wherein the first network and the second network are each a network selected from the group consisting of a CDMA network, a Local Area Network (LAN), a wireless LAN, a global computer network, a General Packet Radio Service (GPRS) network, a Global System for Mobile Communication (GSM) network, a Universal Mobile Telecommunications System (UMTS) network, and the Public Switched Telephone Network (PSTN).

39. The computer-readable medium as defined in claim 31, further comprising discovering the second network before the second communication link is established.

40. The computer-readable medium as defined in claim 39, further comprising determining whether the second network should be used before the second communication link is established through use of network preference criteria.

41. The computer-readable medium as defined in claim 31, wherein the second user agent comprises a legacy user agent and wherein a network application gateway facilitates the soft handoff from the first network to the second network.

42. The computer-readable medium as defined in claim 31, wherein the negotiating is performed before the establishing of the second communication link.

43. The computer-readable medium as defined in claim 31, wherein the negotiating is performed during the establishing of the second communication link.

44. The computer-readable medium as defined in claim 31, wherein the negotiating is performed after the establishing of the second communication link.

45. A computer-readable medium for storing program data, wherein the program data comprises executable instructions for implementing a method in a communication device, the method comprising:

communicating between a first user agent and a second user agent using a first communication link through a first network;

negotiating to use a second communication link for the same call;

establishing the second communication link through a second network between a third user agent and the second user agent while maintaining the first communication link;

sending related data through the first communication link and the second communication link such that the related data is for the same call;

dropping the first communication link; and

continuing communication using the second communication link between the third user agent and the second user agent.