Patent ID: 8189544

Claim:
A method of establishing a security binding between a home agent and an access gateway on behalf of a served mobile station in a Mobile IP network, comprising: obtaining, at the access gateway, an initial root key from an authentication server, wherein the initial root key is used only one time to effectuate an initial security binding; computing, at the access gateway, a derivative key, the derivative key computed as a pseudo-random function of (1) the initial root key, (2) an address of the access gateway and (3) an address of an associated home agent; requesting, by the access gateway, a binding between the home agent and the access gateway on behalf of the mobile station wherein the derivative key is attached to the binding request for authentication of the request; and receiving confirmation at the access gateway from the home agent that the binding request has been validated, wherein confirmation includes a next root key to be used only one time to effectuate a subsequent binding of the mobile station; and replacing, at the access gateway, the initial root key with the next root key.