Method and Apparatus for Mobility Agent Recovery

• US 20110202664A1
• Filed: 04/21/2011
• Published: 08/18/2011
• Est. Priority Date: 03/26/2008
• Status: Active Grant

• Current Assignee: Chandramouli Balasubramanian, Janaradan Ramesh, Vamsidhar Valluri, Venkatesan Pradeep
• Original Assignee: Chandramouli Balasubramanian, Janaradan Ramesh, Vamsidhar Valluri, Venkatesan Pradeep
• Inventors: Pradeep, Venkatesan, Valluri, Vamsidhar, Balasubramanian, Chandramouli, Ramesh, Janaradan
• Granted Patent: US 8,682,861 B2
• Time in Patent Office: Days
• US Class Current: 709/227
• 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

Techniques for recovering Mobile Internet Protocol (IP) session(s) of a mobility agent in a Mobile IP network are described herein. In one embodiment of the invention, for each mobility session associated with a mobility agent, the mobility agent distributively backs up mobility agent specific information to the mobility agent peer associated with that mobility session. The mobility agent specific information is not used by the mobility agent peer. Upon the mobility agent inadvertently losing at least one mobility session, the mobility agent recovers the stored mobility agent specific information associated with those sessions from the mobility agent peers respectively associated with those sessions. Other methods and apparatuses are also described.

Claims

1. A computer implemented method for recovering Mobile Internet Protocol (IP) sessions of a network element in a Mobile IP network, comprising:

receiving a first Mobile IP registration request message from a first foreign agent indicating that a mobile node is requesting Mobile IP services from a home agent provisioned within the network element, wherein the first foreign agent is a mobility agent peer of the home agent;

upon determining to provide Mobile IP services to the mobile node, storing a Mobile IP session for the mobile node in a Mobile IP data structure that includes Mobile IP information specific to the home agent, wherein the specific home agent Mobile IP information is inapplicable to the first foreign agent;

transmitting a first Mobile IP registration response message to the first foreign agent;

modifying the Mobile IP session associated with the mobile node in the Mobile IP session data structure in response to receiving a second Mobile IP registration request message from a second foreign agent, the request message indicating that the mobile node is requesting Mobile IP services from the home agent, wherein the second Mobile IP registration request is at a later time than the first Mobile IP registration request, and wherein the second foreign agent is a mobility agent peer of the home agent;

transmitting a second Mobile IP registration response message to the second foreign agent;

upon the home agent inadvertently losing at least a portion of information stored in the Mobile IP data structure associated with the mobile node, recovering the Mobile IP session,

determining that the second foreign agent is providing Mobile IP services to the mobile node and the first foreign agent is no longer providing Mobile IP services to the mobile node, and

directing the first foreign agent to remove Mobile IP information associated with the mobile node.

2. The computer implemented method of claim 1, wherein the home agent specific Mobile IP information is piggybacked with the transmission of the first and second Mobile IP registration response message to the first and second foreign agent respectively, and wherein recovering the Mobile IP session further comprises,

requesting from the first and second foreign agents the specific home agent Mobile IP information associated with the home agent,

receiving from the first and second foreign agents the specific home agent Mobile IP information that was transmitted by the home agent, and

reconstructing the Mobile IP session associated with the mobile node with the Mobile IP information received from the second foreign agent.

3. The computer implemented method of claim 1, wherein the home agent specific information is transmitted to a second network element, wherein the second network element is a backup of the network element, and wherein recovering the Mobile IP session further comprises,

requesting from the second network element the home agent specific information and

receiving the requested home agent specific information and reconstructing the Mobile IP session associated with the mobile node with that home agent specific information.

4. The computer implemented method of claim 1, wherein determining that the second foreign agent is providing Mobile IP services to the mobile node and the first foreign agent is no longer providing Mobile IP services to the mobile node further comprises,

determining that the second foreign agent started providing Mobile IP services to the mobile node later in time than the first foreign agent.

5. The computer implemented method of claim 1, wherein the home agent directs the foreign agent to remove foreign agent specific information associated with the mobile node and home agent specific information associated with the mobile node.

6. The computer implemented method of claim 2, further comprising prior to transmitting the home agent specific information to the first and second foreign agent, encrypting the home agent specific information in such a way that it is intended that the first and second foreign agent cannot read the home agent specific information, and upon receipt of the home agent specific information from the first and second foreign agents, decrypting the home agent specific information.

7. The computer implemented method of claim 1, further comprising negotiating a set of one or more capabilities with the first and second foreign agent, wherein each capability represents a particular set of one or more operations providing functionality of an application feature, wherein the negotiated capabilities include Mobile IP session recover capability, wherein Mobile IP session recover capability is supported by the home agent and the first and second foreign agents.