Recommendation ITU-T H.248.78 defines a package that allows bearer-level application protocol (such as real time streaming protocol (RTSP) or message sending relay protocol (MSRP)) messages received by a media gateway (MG) to be communicated to a media gateway controller (MGC). This allows the MGC to perform application-level gateway functionality such as network address translation on the messages and then forward the messages to the MG for sending to the destination.