Multi-Tech Systems MVP-2410, MVP-2400, MVP-3010 Gatekeeper Protocols, Gatekeeper services, 484

Embedded Gatekeeper MultiVOIP User Guide

•Gatekeeper services

Built-in services such as call forward, zones and exit zone; and custom services.

The Gatekeeper Protocols

H.323 is an umbrella standard that consists of many subordinate protocols. Three protocols, Q.931, H.225, and H.245, are particularly relevant to gatekeepers.

The Q.931 protocol pertains to the setup and teardown of call connections between network endpoints.

The H.225 Call Signaling Protocol pertains to Registration, Admission, and Status (RAS). (Note that RAS in H.323 has nothing to do with the Remote Access Service that is used in ordinary TCP/IP networks.) H.323 RAS messages are concerned with general participation on the network (registration), specific involvement in particular calls between endpoints within and perhaps outside of the network zone (admission), and the status of endpoints (e.g., are they still “alive” or participating?).

H.245 is the conference control protocol. It pertains to negotiation between endpoints to establish a compatible set of media capabilities.

Because many user-settable parameters of the MultiTech gatekeeper software refer directly or indirectly to the H.225 protocol, we present a summary of common H.225 messages below.

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