The present invention provides a method, system and apparatus for providing security in an unlicensed mobile access network or a generic access network by receiving a message containing a mobile identity of a mobile station (MS) and dropping or rejecting the message whenever the received mobile identity does not match a stored mobile identity associated with the MS. The message is processed whenever the received mobile identity matches the stored mobile identity associated with the MS. The stored mobile identity is provided by a secure gateway. The mobile identity can be an International Mobile Subscriber Identity, Temporary Mobile Subscriber Identity, Packet Temporary Mobile Subscriber Identity, private Internet Protocol (IP) address or public IP address. The message can be a registration request, uplink message or a downlink message, such as a Mobility Management message, a General Packet Radio Service Mobility Management message, or a UMA or Unlicensed Radio Resources message.