Patent ID: 8533455

Claim:
A method for combining internet protocol layer authentication and mobility signaling using a packet data network gateway, comprising: receiving a master key derived from a session (K_ASME) key and a first interface identifier; storing the master key and the first interface identifier in the packet data network gateway; after a mobile node moves from a 3GPP access network to a non-3GPP access network, receiving a router solicitation and a second interface identifier from the mobile node, via an access router in the non-3GPP access network, where the first interface identifier and the second interface identifier are identical; and validating an integrity of the router solicitation using the master key, the first interface identifier, and the second interface identifier; generating a new interface identifier; storing the new interface identifier in the packet data network gateway by replacing the stored first interface identifier; generating a roaming key from the master key; forwarding the roaming key and a router advertisement to the mobile node, via the access router, enabling all subsequent messages to the mobile node to be integrity protected.