MGCP is used with regard to VoIP system

It is an internal protocol primarily developed to meet the demands of IP telephone networks and other carrier-based networks.

Media Gateway Control Protocol can be used for H.323 and SIP and is designed as an in-between protocol of Media Gateway Controller and Media Gateway.

In MGCP the Media Gateway Controller handles the call processing by connecting with the IP network through uninterrupted communications through IP signaling devices like H.323 gatekeeper and SIP Server.

The main components of MGCP VoIP are the Call agent, the Media Gateway and the Signaling Gateway.

The media gateway carries on the process of converting media signals between packets and circuits. The call agent comprises of the call control “intelligence” and along with the media gateway supports the media functions like converting TDM voice to VoIP.

The signaling gateway connects to the Public Switched Telephone Network (PSTN). The media gateway boasts endpoints through the Call Agent creating and managing media sessions with the endpoints of other multimedia.

Endpoints are sources of data which are either physical or virtual in nature. Physical endpoints are created by hardware installation while virtual endpoints are created by software installed on the system.

Call agents are capable of creating new connection and modifying existing ones.

Normally the network element is provided by the media gateway which helps in conversion of the data packets passed through the Internet and other networks to voice signals as is carried by the telephone lines.

The call agent instructs the endpoints to check regularly for events and create signals when any event occurs.

The endpoints automatically communicate to the call agents any changes in service state. The call agents audit the endpoints and the connections leading to them.

The other terminologies related to MGCP VoIP are connections and architecture.

MGCP Connections

These can be from one point to another or to multipoint. In the point to point type, connection is established between two endpoints over which data is transmitted.

In the multipoint connection, connection is established between one endpoint on one side and multipoint session on the other. This type of connection is created over different types of bearer networks.

Media Gateway Control Protocol Architecture

MGCP application is the most sought after especially in VoIP as it does not involve any encoding, decoding and then transfer of voice signals. This can be quite frustrating and time consuming.

The MGCP works much like a software switch for the Internet telephone network, but its basic function is to direct media and signaling gateways which actually do the transmission job.

The call agent’s main job is to implement numerous possibilities for the internal protocol. Various informational RFCs make up for its typical behavior under various conditions.

The MGCP architecture is designed such that each and every command has a transaction ID, acquires an acknowledgement and obtains a response.

It is also referred to as subscription architecture wherein the call agent communicates with the media and signaling gateways about the events it is taking care of and the ones that it is leaving unattended.