Avaya 555-245-600 manual Call Processing, Communication Manager gatekeepers

Call Processing

Call Processing

Communication Manager gatekeepers

A gatekeeper is an H.323 entity on the network that provides address translation and controls access to the network for H.323 endpoints. For Communication Manager platforms, these are the Avaya S8300, S8400, S8500, and S8700-series Servers. H.323 RAS (Registration, Admission, and Status) Protocol messages are exchanged between the server and the IP endpoints for the endpoint registration.

All H.323 voice applications (IP Softphones, IP agents, and IP Telephones) should register with an Avaya gatekeeper before any calls are attempted. Communication Manager sets up call signaling (Q.931) and call control (H.245) channels from endpoints to the gatekeeper. This allows Communication Manager to provide many of its calling features to H.323 calls.

Registration and alternate gatekeeper list

The RAS protocol is used by the IP endpoint to discover and register with the Communication Manager gatekeeper.

When registration with the original gatekeeper (C-LAN, S8500 or S8300) IP address is successful, the switch sends back the IP addresses of all the C-LANs (or LSPs) in the IP Telephone’s network region. These addresses are used if the call signaling to the original C-LAN circuit pack fails. Figure 47: Discovery and registration process to the gatekeeper on page 128 shows the registration process.

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