What is Media Gateway Control Protocol (MGCP)?

The Media Gateway Control Protocol (MGCP) is a signaling protocol used in telecommunication networks to control and manage media gateways. It establishes and maintains communication sessions between media gateways and call control entities, such as call agents or softswitches, in order to enable voice and multimedia services.

Key aspects and functions of the Media Gateway Control Protocol (MGCP)

• Call Setup and Teardown: MGCP is responsible for the setup and teardown of voice and multimedia communication sessions. It facilitates the establishment of connections between media gateways and call control entities, enabling the initiation and termination of calls.
• Media Gateway Control: MGCP provides control and management capabilities for media gateways. It allows call control entities to instruct media gateways on how to process media streams, including voice encoding/decoding, call routing, media conversion, and other functions.
• Call Features and Services: MGCP supports various call features and services, such as call hold, call transfer, conference calling, call forwarding, and voice prompts. Call control entities can use MGCP to manage these features on media gateways during active calls.
• Endpoint Control: MGCP enables control over individual endpoints or interfaces within a media gateway. This includes the management of physical or virtual ports, controlling their availability and configuration, and handling media stream routing to and from these endpoints.
• Signaling Interaction: MGCP is an external control protocol, meaning that it relies on a separate entity (the call control entity) to provide call control and call processing intelligence. The call control entity uses MGCP to communicate with media gateways, sending commands and receiving responses or notifications.
• Protocol Scalability: MGCP is designed for scalability and supports the distributed control of media gateways. It allows for the centralization of call control intelligence while distributing media processing across multiple gateways, enabling efficient resource utilization and load balancing.
• Protocol Architecture: MGCP follows a client-server architecture. The call control entity acts as the client, while the media gateway functions as the server. The client sends commands to the server using MGCP messages to control and manage media gateway resources.

MGCP is often used in conjunction with other protocols and technologies in telecommunication networks, such as the Session Initiation Protocol (SIP) or H.323 for call control, and Real-time Transport Protocol (RTP) for media transport. It is commonly employed in Voice over IP (VoIP) and IP-based telephony systems to facilitate control and management of media gateways, enabling the delivery of voice and multimedia services.