Description and validation of the media gateway control protocol (MGCP) using SDL/MSC

The media gateway control protocol (MGCP) is a protocol for controlling voice over IP (VoIP) gateways. The control is exercised from external call control elements called media gateway controllers (MGCs) or call agents (CAs). The operation of call agents and media gateways, and their interactions via the MGCP, have been modelled using SDL. The checking of general properties of the model were performed using the ObjectGEODE tool. A specific scenario, specified using MSCs, was used as a case study to validate our design against some of the specific properties of the MGCP protocol. The use of SDL/MSC simplifies the description and validation of the protocol, and facilitates the possibility for future extensions of our model.