Method for providing home agent geographic redundancy via a service redundancy protocol

• US 20070116020A1
• Filed: 11/23/2005
• Published: 05/24/2007
• Est. Priority Date: 11/23/2005
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Ramankutty, Rajesh, Cheever, Greg, Puthiyandyil, Sanil
• Granted Patent: US 8,223,687 B2
• Time in Patent Office: Days
• US Class Current: 370/401
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06
• CPC Class Codes: H04W 8/065 involving selection of the user mobility server
• CPC Class Codes: H04W 8/12 between location registers or mobility servers
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

Methods and systems for providing redundancy in servicing packet data communications within wireless mobile data networks are disclosed. More particularly, the method and system provide a redundant Home Agent with the ability to assume the role of the primary Home Agent in the event of a primary Home Agent network, software, or other failure. The redundancy allows the Home Agent services to remain functional even in the event of a failure of one of the Home Agents in the redundant group, which may be composed of one or more Home Agents. The Home Agents can use a service redundancy protocol which is composed of messages that are sent between the redundant group of Home Agents. The messages allow the Home Agents to, for example, back up call session information, check on the status of one another, and share priority information.

Claims

1. A system for providing communication between Home Agents comprising:

a first Home Agent acting as a primary Home Agent;

a second Home Agent communicating with the first Home Agent;

a communication link coupling the first and second Home Agent;

the first Home Agent being able to send a Hello Message to the second Home Agent, the Hello Message containing system attributes;

the first Home Agent being able to send a Service Checkpoint Message to the second Home Agent which provides information used to perform as the primary Home Agent; and

the second Home Agent being able, in response to at least one of the Hello Message and the Service Checkpoint Message, to transition to become the primary Home Agent.

2. The system of claim 1, wherein the communication link is a redundancy link.

3. The system of claim 1, wherein the Hello Message and the Service Checkpoint Message are formatted in accordance with a Transfer Control Protocol (TCP) based networking protocol.

4. The system of claim 1, wherein the second Home Agent transitions to the primary Home Agent based on information in the Hello Message.

5. The system of claim 1, wherein the system attributes of the Hello Message are Home Agent state, Priority, and BGP modifier.

6. The system of claim 1, wherein the second Home Agent after transitioning to the primary Home Agent advertises identification information of the first Home Agent.

7. The system of claim 6, wherein the identification information includes IP Pool and loopback interface routes.

8. A method for providing communication between Home Agents comprising:

sending a Hello Message containing system attributes from a first Home Agent to a second Home Agent;

sending a Service Checkpoint Message from the first Home Agent acting as a primary Home Agent to the second Home Agent, wherein the Service Checkpoint Message contains information used to perform as the primary Home Agent; and

transitioning the second Home Agent to the primary Home Agent.

9. The method of claim 8, wherein the communication occurs through a redundancy link.

10. The method of claim 8, further comprising sending the Hello Message and the Service Checkpoint Message using a Transfer Control Protocol (TCP) based networking protocol.

11. The method of claim 8, wherein the transitioning step is based on information in the Hello Message.

12. The method of claim 8, wherein the system attributes of the Hello Message are Home Agent state, Priority, and BGP modifier.

13. The method of claim 8, further comprising advertising identification information of the first Home Agent after the second Home Agent transitions to the primary Home Agent.

14. The method of claim 13, wherein the identification information includes IP Pool and loopback interface routes.

15. A system for providing communication between Home Agents comprising:

a first means for providing a primary Home Agent;

a second means for providing a second Home Agent;

a means for communicating between the first means and the second means;

the first means sending a Hello Message to the second means, the Hello Message containing system attributes; and

the first means sending a Service Checkpoint Message to the second means providing information used to perform as the primary Home Agent,

wherein the second means transitions to become the primary Home Agent.

16. The system of claim 15, wherein the communication means is a redundancy link.

17. The system of claim 15, wherein the Hello Message and the Service Checkpoint Message are a Transfer Control Protocol (TCP) based networking protocol.

18. The system of claim 15, wherein the second means transitions to the primary Home Agent based on information in the Hello Message.

19. The system of claim 15, wherein the system attributes of the Hello Message are Home Agent state, Priority, and BGP modifier.

20. The system of claim 15, wherein the second means after transitioning to the primary Home Agent advertises identification information of the first means through the communication means.

21. The system of claim 20, wherein the identification information is IP Pool and loopback interface routes.