Delegation based mobility management

A mobile router in a communications system, the mobile router comprising:

• a processor;
• and
• a memory that stores processor-executable instructions where the processor interfaces with the memory and executes the processor-executable instructions to perform operations as follows:
• receiving a delegation certificate that is cryptographically signed by or on behalf of the mobile node;
• maintaining a sequence number counter associated with said certificate and for incrementing the sequence number counter for each mobility-related signaling exchange conducted by the mobile router with a given peer node on behalf of the mobile node;
• initiating a mobility-related signaling exchange with the peer node on behalf of the mobile node and for providing to the peer node within this exchange, said delegation certificate or an identification of the certificate and the sequence number currently held by said sequence number counter;
• and
• wherein the sequence number counter is dedicated to keeping track of a number of mobility-related signaling exchanges conducted by the mobile router with the given peer node on behalf of the mobile node.

A method of operating a mobile router within a communications system, the method comprising:

• receiving, by the mobile router, a delegation certificate that is cryptographically signed by or on behalf of the mobile node;
• maintaining, by the mobile router, a sequence number counter associated with said certificate and incrementing the sequence number counter for each mobility-related signaling exchange conducted by the mobile router with a peer node on behalf of the mobile node;
• initiating, by the mobile router, a mobility-related signaling exchange with the peer node on behalf of the mobile node, and providing to the peer node within this exchange, said delegation certificate or an identification of the certificate, and the sequence number currently held by said sequence number counter;
• and
• wherein the sequence number counter is dedicated to keeping track of a number of mobility-related signaling exchanges conducted by the mobile router with the peer node on behalf of the mobile node.

A peer node in a communications system, the peer node comprising:

• a processor;
• and
• a memory that stores processor-executable instructions where the processor interfaces with the memory and executes the processor-executable instructions to perform operations as follows:
• conducting a mobility-related signaling exchange with a mobile router acting on behalf of a mobile node, said means receiving within this exchange, a delegation certificate or an identification of the certificate and a sequence number associated with the certificate;
• maintaining a sequence number counter associated with said certificate and for incrementing the sequence number counter for each mobility-related signaling exchange conducted with said mobile router acting on behalf of the mobile node;
• and
• comparing the received sequence number with the sequence number held by the sequence number counter, and for authorizing the mobility-related signaling exchange in dependence upon the result of the comparison;
• and
• wherein the sequence number counter is dedicated to keeping track of a number of mobility-related signaling exchanges conducted by the mobile router with the peer node on behalf of the mobile node.

A method of operating a peer node in a communications system, the method comprising:

• conducting, by the peer node, a mobility-related signaling exchange with a mobile router acting on behalf of a mobile node including receiving within this exchange a delegation certificate or an identification of the certificate, and a sequence number associated with the certificate;
• maintaining, by the peer node, a sequence number counter associated with said certificate and incrementing the sequence number counter for each mobility-related signaling exchange conducted with said mobile router acting on behalf of the mobile node;
• comparing, by the peer node, the received sequence number with the sequence number held by the sequence number counter, and authorizing, by the peer node, the mobility-related signaling exchange in dependence upon the result of the comparison;
• and
• wherein the sequence number counter is dedicated to keeping track of a number of mobility-related signaling exchanges conducted by the mobile router with the peer node on behalf of the mobile node.