A system and method for updating a security key at a base station (BS) is disclosed. The method comprises the operation of transmitting a handover command from the base station to a mobile station. The operation of incrementing a base station instance of an authentication key counter at the base station follows. The next operation of the method can be calculating a new local authentication key (AK*) at the base station using the base station instance of the authentication key counter and an authentication key (AK). The AK may be previously obtained from an authenticator. The method further includes communicating by the base station with the mobile station using the new local authentication key after a predetermined action time.