US Patent 7813511 Facilitating mobility for a mobile station

Providing a mobility key for a communication session for a mobile station includes facilitating initiation of the communication session. A master key for the communication session is established, where the master key is generated at an authentication server in response to authenticating the mobile station. A mobility key is derived from the authentication key at an access node, where the mobility key is operable to authenticate mobility signaling for the communication session.