Simple Gateway Control Protocol

Simple Gateway Control Protocol (SGCP) is a communications protocol used within a Voice over Internet Protocol (VoIP) system. It has been superseded by MGCP, an implementation of the Media Gateway Control Protocol Architecture.

The Simple Gateway Control Protocol was published in 1998 by Christian Huitema and Mauricio Arango, as part of the development of the "Call Agent Architecture" at Telcordia Technologies (formerly Bellcore). In this architecture a call-control elements, Media Gateway Controllers (MGCs) or the Call Agent, controls trunking, residential, and access-type VoIP "media gateways" and receives telephony signaling requests through a "signalling gateway".Although these gateways target different market segments, all of them convert time-division multiplexing (TDM) voice to packet voice. Later implementation of the architecture refer to the "Call Agent" as a "Softswitch".