Method and apparatus for effecting a handoff between two IP connections for time critical communications

• US 20040030791A1
• Filed: 08/06/2002
• Published: 02/12/2004
• Est. Priority Date: 08/06/2002
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Dorenbosch, Jheroen P., Raymer, David L.
• Granted Patent: US 6,850,503 B2
• Time in Patent Office: Days
• US Class Current: 709/230
• CPC Class Codes: H04W 36/0033 with transfer of context information
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 80/06 Transport layer protocols, e.g. TCP [Transport Control Protocol] over wireless transmission control protocol/Internet protocol [TCP/IP] or user datagram protocol [UDP] H04L69/16
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

A method 900 of and wireless communications unit 800 for effecting a handoff from a first Internet Protocol (IP) connection 221 to a second IP connection 331 for a time critical communication is disclosed. The method includes communicating 905 between a first wireless station 219 and a second station 331 using the first IP connection and a first IP address 223 for the first wireless station; setting up 907 the second IP connection with a second IP address for the first wireless station, the first IP connection being a primary connection and the second IP connection being a secondary connection, both existing concurrently; determining 915 that the second IP connection should be the primary connection; and changing 917 the second IP connection to the primary connection by informing the second station that the second IP address is the primary address using stream control transmission protocol (SCTP) messages, wherein the time critical communication is immediately switched over to the second IP connection.

Claims

1. A method of effecting a handoff from a first Internet Protocol (IP) connection to a second IP connection for a time critical communication, the method comprising:

communicating between a first wireless station and a second station using the first IP connection and a first IP address for the first wireless station;

setting up the second IP connection with a second IP address for the first wireless station, the first IP connection being a primary connection and the second IP connection being a secondary connection, both existing concurrently;

determining that the second IP connection should be the primary connection; and

changing the second IP connection to the primary connection by informing the second station that the second IP address is the primary address using stream control transmission protocol (SCTP) messages,

wherein the time critical communication is immediately switched over to the second IP connection.

2. The method of claim 1 wherein said communicating between said first wireless station and said second station using the first IP connection further uses a cellular base station, said communicating supported by an application on the first wireless station that runs on SCTP.

3. The method of claim 2 further including informing said second station of the first IP address using SCTP before starting said communicating.

4. The method of claim 2 wherein said setting up the second IP connection further includes searching for an appropriate connection, associating with a wireless IP access point, and establishing connectivity with the second station by informing said second station of the second IP address using SCTP.

5. The method of claim 4 wherein said searching, said associating, and said establishing are undertaken independent of said application supporting said communicating.

6. The method of claim 4 wherein said searching for said appropriate wireless IP connection further includes one of determining that an available connection includes an access point and suitable services, that said first wireless station is able to successfully authenticate with said access point, and that connectivity to said second station is available.

7. The method of claim 4 wherein said associating with a wireless IP access point further includes associating with one of an 802.11 access point, a Bluetooth access point, a HiperLAN access point, and a local area network (LAN) access point.

8. The method of claim 4 wherein said informing said second station of the second IP address using SCTP uses said second connection thereby initializing said second connection.

9. The method of claim 2 wherein said determining that the second IP connection should be the primary connection further includes one of determining that a signal from said cellular base station is weakening, that tariffs for the second IP connection are favorable, and that services are desired that are available via the second IP connection.

10. The method of claim 2 further including, when the second IP connection becomes the primary connection, discontinuing the first IP connection.

11. The method of claim 10 wherein said discontinuing the first IP connection further includes instructing the second station to delete the first IP address using SCTP messages and terminating any session via said cellular base station.

12. The method of claim 1 wherein said communicating between said first wireless station and said second station using the first IP connection further uses a first wireless IP access point, said communicating supported by an application on the first wireless station that runs on SCTP.

13. The method of claim 12 further including informing said second station of the first IP address using SCTP before starting said communicating.

14. The method of claim 12 wherein said setting up the second IP connection further includes searching for an appropriate wireless IP connection, associating with a second wireless IP access point, and establishing connectivity with the second station by informing said second station of the second IP address using SCTP.

15. The method of claim 14 wherein said searching, said associating, and said establishing are undertaken independent of said application supporting said communicating.

16. The method of claim 14 wherein said searching for said appropriate wireless IP connection further includes one of determining that an available wireless IP connection includes a wireless IP access point and suitable services, that said first wireless station is able to successfully authenticate with said access point, and that connectivity to said second station is available.

17. The method of claim 14 wherein said associating with said second wireless IP access point further includes associating with one of an 802.11 access point, a Bluetooth access point, a HiperLAN access point, and a local area network (LAN) access point.

18. The method of claim 14 wherein said informing said second station of the second IP address using SCTP uses said second connection thereby initializing said second connection.

19. The method of claim 12 wherein said determining that the second IP connection should be the primary connection further includes one of determining that a signal from said first wireless IP access point is weakening, that loading levels for the second IP connection are favorable, and that services are desired that are available via the second IP connection.

20. The method of claim 12 further including, when the second IP connection becomes the primary connection, discontinuing the first IP connection by instructing the second station to delete the first IP address using SCTP messages and disassociating with said first wireless access point.

21. The method of claim 2 wherein said setting up the second IP connection further includes searching for an appropriate cellular connection, establishing a connection with a second cellular base station, and establishing connectivity with the second station by informing said second station of the second IP address using SCTP.

22. The method of claim 12 wherein said setting up the second IP connection further includes searching for an appropriate cellular connection, establishing a connection with a second cellular base station, and establishing connectivity with the second station by informing said second station of the second IP address using SCTP.

23. A wireless communications unit arranged and constructed to effect a handoff from a first Internet Protocol (IP) connection to a second IP connection for a time critical communication, the wireless communications unit comprising:

a wireless transceiver and a controller cooperatively arranged for communicating with a second station using the first IP connection and a first IP address for the wireless communications unit;

said controller further for;

setting up the second IP connection with a second IP address for the wireless communications unit, the first IP connection being a primary connection and the second IP connection being a secondary connection, both existing concurrently;

determining that the second IP connection should be the primary connection; and

changing the second IP connection to the primary connection by informing the second station that the second IP address is the primary address using stream control transmission protocol (SCTP) messages,

wherein the time critical communication is immediately switched over to the second IP connection.

24. The wireless communications unit of claim 23 wherein said wireless transceiver includes a cellular transceiver for communicating with said second station using the first IP connection through a cellular base station, said communicating supported by an application executed by said controller, said application running on SCTP.

25. The wireless communications unit of claim 24 further including informing said second station of the first IP address using SCTP before starting said communicating.

26. The wireless communications unit of claim 24 wherein said transceiver further includes a wireless IP transceiver cooperatively operating with said controller for setting up the second IP connection and further for searching for an appropriate wireless IP connection, associating with a wireless IP access point, and establishing connectivity with the second station by informing said second station of the second IP address using SCTP.

27. The wireless communications unit of claim 26 wherein said searching, said associating, and said establishing are undertaken independent of said application supporting said communicating.

28. The wireless communications unit of claim 26 wherein said searching for said appropriate wireless IP connection further includes one of determining that an available connection includes an access point and suitable services, that said first wireless station is able to successfully authenticate with said access point, and that connectivity to said second station is available.

29. The wireless communications unit of claim 26 wherein said associating with a wireless IP access point further includes associating with one of an 802.11 access point, a Bluetooth access point, a HiperLAN access point, and a local area network (LAN) access point and said transceiver further includes a second transceiver, respectively compatible with one of 802.11, Bluetooth, HiperLAN, and local area network systems.

30. The wireless communications unit of claim 26 wherein said informing said second station of the second IP address using SCTP uses said second transceiver and said second connection thereby initializing said second connection.

31. The wireless communications unit of claim 24 wherein said determining that the second IP connection should be the primary connection further includes one of determining that a signal from said cellular base station is weakening, that tariffs for the second IP connection are favorable, and that services are desired that are available via the second IP connection.

32. The wireless communications unit of claim 24 further including, when the second IP connection becomes the primary connection, discontinuing the first IP connection by instructing, using SCTP messages, the second station to delete the first IP address and terminating any session via said cellular base station.

33. The wireless communications unit of claim 23 wherein said wireless transceiver includes a wireless IP transceiver for communicating with said second station using the first IP connection through a wireless IP access point, said communicating supported by an application executed by said controller, said application running on SCTP.

34. The wireless communications unit of claim 33 further including informing said second station of the first IP address using SCTP before starting said communicating.

35. The wireless communications unit of claim 33 wherein said wireless IP transceiver cooperatively operates with said controller for setting up the second IP connection and further for searching for an appropriate wireless IP connection, associating with a second wireless IP access point, and establishing connectivity with the second station by informing said second station of the second IP address using SCTP.

36. The wireless communications unit of claim 35 wherein said searching, said associating, and said establishing are undertaken independent of said application supporting said communicating.

37. The wireless communications unit of claim 35 wherein said searching for said appropriate wireless IP connection further includes one of determining that an available wireless IP connection includes a wireless IP access point and suitable services, that said first wireless station is able to successfully authenticate with said access point, and that connectivity to said second station is available.

38. The wireless communications unit of claim 35 wherein said associating with said second wireless IP access point further includes associating with one of an 802.11 access point, a Bluetooth access point, a HiperLAN access point, and a local area network (LAN) access point and said transceiver further includes a second transceiver respectively compatible with one of 802.11, Bluetooth, HiperLAN, and local area network systems.

39. The wireless communications unit of claim 35 wherein said informing said second station of the second IP address using SCTP uses said second transceiver and said second connection thereby initializing said second connection.

40. The wireless communications unit of claim 33 wherein said determining that the second IP connection should be the primary connection further includes one of determining that a signal from said first wireless IP access point is weakening, that loading levels for the second IP connection are favorable, and that services are desired that are available via the second IP connection.

41. The wireless communications unit of claim 33 further including, when the second IP connection becomes the primary connection, discontinuing the first IP connection by instructing the second station to delete the first IP address and disassociating with said first wireless access point.