This Recommendation defines packages and mechanisms for supporting the interconnection of a packet network with another network. The packages defined by this Recommendation are only applicable to IP-based ITU-T H.248 terminations. The packages are therefore applicable for: ?C IP-to-IP ITU-T H.248 media gateways@ and ?C IP-to-non-IP ITU-T H.248 media gateways. Specifying the IP realm of an ITU-T H.248 stream The media gateway controller (MGC) may specify the IP realm/s that a stream of a particular ITU-T H.248 termination belongs to. This is accomplished through the IP Realm Identifier property of the IP Domain Connection package. Auditing the MG supported realms and their availability Auditing all supported realms The MGC can audit the realms supported by the MG (i.e.@ all realms that the MG is aware of) by using an AuditCapabilities on the IP Realm Identifier property of the IP Domain Connection package. Understanding the availability of realms The IP Realm Availability package extends the IP Domain Connection package. Through an AuditValue of this package's Available Realms property@ the MGC is able to learn which of the supported realms is currently available (i.e.@ over which realms the MG can currently send and receive traffic). Similarly@ the MGC may request to be notified of changes to the list of available realms through the Available Realms Changed event of the same package.