Handoff decision making for heterogeneous network environments

• US 20070076664A1
• Filed: 09/30/2005
• Published: 04/05/2007
• Est. Priority Date: 09/30/2005
• Status: Abandoned Application

• Current Assignee: Stoke Incorporated (Mavenir Group Holdings Ltd.)
• Original Assignee: Stoke Incorporated (Mavenir Group Holdings Ltd.)
• Inventors: Gallagher, Mark, Baw, Allan, An, Yafan
• Application Number:
  US11/242,367
• Publication Number:
  US 20070076664A1
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 67/147 Signalling methods or messages providing extensions to protocols defined by standardisation
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 80/10 adapted for application session management, e.g. SIP [Session Initiation Protocol] connection management H04W76/00; arrangements for session management H04L67/14

Abstract

A method and apparatus of handoff decision making for heterogeneous network environments are described. In one embodiment, the method includes receiving session initiation protocol (SIP) messages from a mobile device via a wireless local area network (WLAN). The SIP messages contain data identifying at least one current network characteristic. The method further includes determining whether a handoff trigger for the mobile device is detected using the current network characteristic.

Claims

1. A method comprising:

receiving session initiation protocol (SIP) messages via a wireless local area network (WLAN), the SIP messages comprising data identifying at least one current network characteristic; and

determining whether a handoff trigger for a mobile device is detected using the at least one current network characteristic.

2. The method of claim 1 wherein determining whether the handoff trigger is detected comprises:

comparing the at least one current network characteristic with a threshold.

3. The method of claim 2 wherein the threshold is defined by a carrier.

4. The method of claim 1 wherein determining whether the handoff trigger is detected comprises:

determining whether a wireless local area network (WLAN) providing service to the mobile device is overloaded.

5. The method of claim 1 wherein determining whether the handoff trigger is detected comprises:

determining whether a cell with desired parameters is available in a cellular wide area network (WAN).

6. The method of claim 1 wherein the at least one current network characteristic comprises at least one of a signal strength indicator and an error rate.

7. The method of claim 1 firther comprising:

selecting a target cell to serve the mobile device.

8. The method of claim 7 wherein the target cell is selected based on a mobile device location and characteristics of nearby cells.

9. The method of claim 7 further comprising:

evaluating the target cell based on policy criteria; and

executing a handover from the WLAN to a cellular wide area network (WAN) if the target cell meets the policy criteria.

10. The method of claim 9 wherein the handover policy criteria comprises at least one of a security criterion, a carrier preference and a timing criterion.

11. The method of claim 1 wherein the at least one current network characteristic is included in an attachment of a SIP message.

12. The method of claim 11 wherein a type of the attachment is specified in one of a plurality of header fields of the SIP message.

13. The method of claim 1 further comprising:

receiving a registration message from the mobile device in a roaming mode, the registration message comprising contact information for the mobile device; and

storing the contact information in a SIP register.

14. The method of claim 13 further comprising:

determining, based on the contact information, that a location of the mobile device has changed; and

updating the location of the mobile device in a home location register (HLR).

15. The method of claim 13 wherein the registration message comprises a SIP registration message.

16. An apparatus comprising:

a message receiver to receive session initiation protocol (SIP) messages via a wireless local area network (WLAN), the SIP messages comprising data identifying at least one current network characteristic; and

a handover trigger detector to determine whether a handoff trigger for a mobile device is detected using the at least one current network characteristic.

17. The apparatus of claim 16 wherein the handover trigger determines whether the handoff trigger is detected by comparing the at least one current network characteristic with a threshold.

18. The apparatus of claim 17 wherein the threshold is defined by a carrier.

19. The apparatus of claim 16 wherein the handover trigger determines whether the handoff trigger is detected by determining whether a wireless local area network (WLAN) providing service to the mobile device is overloaded.

20. The apparatus of claim 16 wherein the handover trigger determines whether the handoff trigger is detected by determining whether a cell with desired parameters is available in a cellular wide area network (WAN).

21. The apparatus of claim 16 wherein the at least one current network characteristic comprises at least one of a signal strength indicator and an error rate.

22. The apparatus of claim 16 further comprising a target cell selector to select a target cell to serve the mobile device.

23. The apparatus of claim 16 wherein the at least one current network characteristic is included in an attachment of a SIP message.

24. The apparatus of claim 23 wherein a type of the attachment is specified in one of a plurality of header fields of the SIP message.

25. A system comprising:

means for receiving session initiation protocol (SIP) messages via a wireless local area network (WLAN), the SIP messages comprising data identifying at least one current network characteristic; and

means for determining whether a handoff trigger for a mobile device is detected using the at least one current network characteristic.

26. A computer readable medium comprising executable instructions which when executed on a processing system cause said processing system to perform a method comprising:

receiving session initiation protocol (SIP) messages via a wireless local area network (WLAN), the SIP messages comprising data identifying at least one current network characteristic; and

determining whether a handoff trigger for a mobile device is detected using the at least one current network characteristic.