Megaco

The Gateway Control Protocol (H.248, Megaco) is an implementation of the for providing telecommunication services across a converged internetwork consisting of the traditional public switched telephone network (PSTN) and modern packet networks, such as the Internet. H.248 is the designation of the recommendations developed by the ITU Telecommunication Standardization Sector (ITU-T) and Megaco is an abbreviation used primarily in the Internet Engineering Task Force (IETF). The current standard published in March 2013 by ITU-T is H.248.1: Gateway control protocol: Version 3.

The protocol is used between elements of a physically decomposed multimedia gateway, the media gateway and one or more media gateway controllers, and architecture that separates call control from media conversion between dissimilar networks. H.248/Megaco is a master/slave protocol used to separate the call control logic from the media processing logic in a gateway.

H.248/Megaco follows the guidelines of the API Media Gateway Control Protocol Architecture and Requirements in RFC 2805 (April 2000). Though H.248 performs the same functions as other Media Gateway control protocol namely , it uses different syntax, commands and processes and supports a broader range of networks. H.248 and MGCP protocols are complementary to H.323 and protocols.

The protocol was the result of collaboration of the MEGACO working group of the Internet Engineering Task Force (IETF) and International Telecommunication Union Telecommunication Study Group 16. The IETF originally published the standard as RFC 3015, which was later replaced by RFC 3525. The term Megaco is the IETF designation. Megaco combines and Media Device Control Protocol (MDCP). in turn was formed by merging (SGCP) with (IPDC).

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