H.248 (also known as the Megaco protocol) is the standard for allowing a media gateway controller (ITU and the IETF. Prior to this effort, there were a number of competing protocols, including (the combination of SGCP and IPDC) and MDCP. This protocol is considered complementary to and , in that an MGC will control MGs using H.248, but will communicate between one another via H.323 or SIP.) to control media gateways ( ). H.248 represents a joint cooperative effort between the
In the diagram below, you can see the timeframes in which the various Media Gateway Control protocols were developed and how those were collapsed into what is now known as H.248.