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An MGCP Profile

MGCP stands for Media Gateway Control Protocol. It's a telecommunications protocol used for controlling media gateways on Internet Protocol (IP) networks.  If you have media gateways in you VoIP network, you need this profile:

If your gateway goes to the PSTN using the C15 protocol, I have a separate profile for that.

Here's a quick breakdown of MGCP:

What MGCP Does:

• It controls voice gateways that convert audio between the public switched telephone network (PSTN) and packet-switched networks like the internet.

• MGCP is a master/slave protocol — the Call Agent (also called a Media Gateway Controller) gives instructions to the Media Gateway, which just follows orders (it doesn’t make decisions on its own).

Where MGCP Fits:

• Used in VoIP (Voice over IP) systems.

• Sits between the signaling layer (like SIP or H.323) and the media layer (RTP streams for actual voice data).

Typical Components in MGCP:

• Call Agent (CA): Central controller that handles call signaling and instructs gateways.

• Media Gateway (MG): Physical or virtual device that converts voice from analog/digital to IP.

• Media Gateway Controller (MGC): Another term for Call Agent.

Why Use MGCP?

• Simplifies gateway devices — all call logic stays in the controller.

• Easier centralized control over complex voice networks.

🛠️ Example Use Case:

• A traditional phone connects to a VoIP network via a gateway. MGCP is used to tell the gateway when to play dial tone, collect digits, start/stop audio streams, etc.

This profile for Wireshark helps you isolate MGCP for troubleshooting.