Patent ID: 7434258

Claim:
A method, comprising: receiving a registration message from a user equipment, wherein the registration message is configured to request registration of the user equipment, and wherein the user equipment is configured to transmit and receive communications; after receiving the registration message, setting a time length of a security association to be equal to a registration time length set for a registration of the user equipment; transmitting the set time length of the security association to the user equipment as part of an acknowledgment message to the registration message to cause the security association to have a time equal to the registration time length; and sending an authentication challenge comprising a temporary timer to the user equipment, preceding the acknowledgment message, which sets a time duration for the user equipment to respond to the authentication challenge, wherein communications with the user equipment comprise a session initiation protocol, wherein the registration message comprises a session initiation protocol register request message, and wherein the acknowledgment message comprises a session initiation protocol response message.