Heuristic algorithm/protocol to determine the nearest available gateway for a mobile client

• US 6,973,313 B1
• Filed: 03/29/2002
• Issued: 12/06/2005
• Est. Priority Date: 03/29/2002
• Status: Expired due to Fees

• Current Assignee: Unwired Planet LLC (JP Morgan Chase & Co)
• Original Assignee: Openwave Systems Incorporated (JP Morgan Chase & Co)
• Inventors: Sebastian, Joby T.
• Primary Examiner(s): Trinh, Sonny
• Assistant Examiner(s): PHAN, HUY Q
• Application Number:
  US10/112,262
• Time in Patent Office: 1,348 Days
• Field of Search: 455/445, 455/432.1, 455/435.2, 455/435.3, 455/436, 455/440, 455/520, 370/353, 370/354, 370/331
• US Class Current: 455/445
• CPC Class Codes: H04L 43/50 Testing arrangements
• CPC Class Codes: H04W 36/00 Hand-off or reselection arrangements
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service

Abstract

A method and apparatus for selecting an optimum gateway for a mobile client are described. The mobile client receives an acknowledgement from a home agent, indicating that the mobile client has moved from the home agent to a foreign agent. An optimum gateway is then determined from several gateways and then selected for the mobile client.

Claims

1. A method comprising:

in response to a mobile client having changed locations, automatically testing each of a plurality of gateways to determine an optimum gateway for the mobile client from the plurality of gateways, wherein said testing includes at least one of (a) determining a number of hops required for a request to travel between a foreign agent and a selected gateway, and (b) determining an elapsed time required for the request to travel between the foreign agent and the selected gateway; and

selecting the optimum gateway for the mobile client.

2. The method of claim 1, wherein testing the selected gateway includes sending the request from a primary gateway, through the foreign agent to the selected gateway.

3. The method of claim 2, wherein the testing produces a plurality of test results and the number of hops and the elapsed time are two of the plurality of test results.

4. The method of claim 1, wherein the foreign agent includes a router.

5. The method of claim 1, wherein the optimum gateway is a wireless gateway.

6. The method of claim 1, wherein the mobile client includes a cellular telephone.

7. The method of claim 1, wherein the mobile client having changed locations comprises the mobile client moving from a home agent to the foreign agent.

8. The method of claim 7, wherein the home agent includes a router.

9. The method of claim 7, wherein the mobile client moving from the home agent to the foreign agent includes:

moving the mobile client from a first network to a second network.

10. The method of claim 1, wherein determining the number of hops required for the request includes examining an IP header of the request.

11. The method of claim 1, wherein determining the elapsed time required for the request includes examining an IP header of the request.

12. A method of selecting a gateway comprising:

testing each of a plurality of gateways to produce a plurality of test results, wherein said testing includes;

selecting a gateway from the plurality of gateways;

sending a request from a primary gateway, through a selected router to the selected gateway;

determining at least one of a group consisting of (a) a number of hops required for the request to travel between the selected router and the selected gateway, and (b) an elapsed time required for the request to travel between the selected router and the selected gateway, wherein the number of hops and the elapsed time are two of the plurality of test results; and

recording the plurality of test results for the selected gateway; and

automatically selecting an optimum gateway from the plurality of gateways, for use by a mobile client, based on results of said testing.

13. The method of claim 12, wherein selecting the optimum gateway includes:

selecting one of the plurality of gateways that has a least number of hops as the optimum gateway.

14. The method of claim 12 wherein selecting the optimum gateway includes:

selecting one of the plurality of gateways that has a least elapsed time as the optimum gateway.

15. The method of claim 12, wherein selecting the optimum gateway includes:

selecting one of the plurality of gateways that has a combination of a least elapsed time and a least number of hops as the optimum gateway.

16. The method of claim 12, wherein selecting the optimum gateway includes:

selecting one of the plurality of gateways that has a function of a least elapsed time and a least number of hops as the optimum gateway.

17. The method of claim 12, wherein the optimum gateway is a wireless gateway.

18. A system comprising:

a processor; and

a storage facility coupled to the processor and containing instructions executable by the processor which configure the system to;

automatically test each of a plurality of gateways, including instructions to;

select a gateway from the plurality of gateways;

test the selected gateway, including instructions to (a) send a request from a primary gateway, through a foreign agent to the selected gateway, (b) determine a number of hops required for the request to travel between the foreign agent and the selected gateway, and (c) determine an elapsed time required for the request to travel between the foreign agent and the selected gateway, wherein the number of hops and the elapsed time are two of a plurality of test results; and

record the plurality of test results for the selected gateway; and

automatically select an optimum gateway from the plurality of gateways.

19. The system of claim 18, wherein the foreign agent includes a router.

20. The system of claim 18, wherein the mobile client includes a cellular telephone.

21. The system of claim 18, wherein the optimum gateway is a wireless gateway.

22. A system for determining an optimum gateway comprising:

a processor; and

a storage facility coupled to the processor and containing instructions executable by the processor which configure the system with;

means for automatically testing each of a plurality of gateways by determining at least one of (a) a number of hops required for a request to travel between a foreign agent and a selected gateway, and (b) an elapsed time required for the request to travel between a foreign agent and a selected gateway; and

means for automatically selecting an optimum gateway from the plurality of gateways.

23. A wireless gateway comprising:

a processor;

a wireless network coupled to the processor;

a storage facility coupled to the processor and containing instructions executable by the processor which configure the wireless gateway to automatically test each of a plurality of gateways, wherein testing each one of the plurality of gateways includes;

selecting a gateway from the plurality of gateways;

sending a request from a primary gateway, through a foreign agent to the selected gateway;

recording a number of hops required for the request to travel between the foreign agent and the selected gateway; and

recording an elapsed time required for the request to travel between the foreign agent and the selected gateway; and

determine one of the plurality of gateways that has a combination of a least elapsed time and a least number of hops to be an optimum gateway.

24. The wireless gateway of claim 23 further comprising:

a mobile client coupled to the wireless network.

25. The wireless gateway of claim 24, wherein the mobile client includes a web enabled cellular telephone.

26. The method of claim 23, wherein the number of hops and the elapsed time is to be determined by examining an IP header of the request.

27. The method of claim 23, wherein determining the optimum gateway further includes determining a geographic location of the foreign agent.

28. The method of claim 23, wherein the optimum gateway is a gateway to the Internet.

29. The method of claim 23, wherein the optimum gateway is a gateway to a software application.

30. A method comprising:

determining that a mobile client has moved from a home agent to a foreign agent;

in response to the mobile client having moved from the home agent to the foreign agent, testing each of a plurality of gateways, wherein testing each of the plurality of gateways includes;

selecting a gateway from the plurality of gateways;

sending a request from a primary gateway, through the foreign agent to the selected gateway;

recording a number of hops required for the request to travel between the foreign agent and the selected gateway; and

recording an elapsed time required for the request to travel between the foreign agent and the selected gateway; and

selecting one of the plurality of gateways that has a combination of a least elapsed time and a least number of hops as an optimum gateway.

31. The method of claim 30, wherein the home agent is a router.

32. The method of claim 30, wherein the foreign agent is a router.

33. The method of claim 30, wherein the mobile client is a wireless telephone.

34. The method of claim 30, wherein determining that the mobile client has moved from the home agent to the foreign agent includes registering the client'"'"'s new address with the home agent.

35. The method of claim 30, wherein testing each of the plurality of gateways is to be initiated by a request from the client.