Service Providers - RADVision L2W-323 User Manual

Overview
Predefined Endpoint Registration
Predefined H.323 endpoints that do not support the RAS protocol are permanently
registered with the Gatekeeper. This does not mean the endpoint is necessarily online. You
can define these types of endpoints as Online Always. The Online Always parameter
indicates to the Gatekeeper that the endpoint is ready to receive calls. If this endpoint is not
defined as Online Always, the Gatekeeper has no way of knowing it is online and will not
route any calls to it. An endpoint not defined as Online Always can, however, initiate calls.
Both online endpoints and predefined endpoints defined as Online Always can receive calls.
Making Calls through the Gatekeeper
Registered H.323 endpoints can communicate with each other and use services the
Gatekeeper makes available. These services may include outbound dialing to a terminal or
phone on the WAN, dialing to other H.323 endpoints on other zones, or forwarding calls to
other destinations. The Gatekeeper's ability to perform address translation simplifies the
dialing procedure.
Address Translation and Aliases
An H.323 endpoint that registers with a Gatekeeper provides an IP address and aliases such
as phone numbers and/or terminal IDs (names). The Gatekeeper can translate between the
IP address and the corresponding aliases. This enables users to dial a number or character
string when dialing to other endpoints, instead of the IP address.
When you want to reach another endpoint in the Gatekeeper zone, simply dial that endpoint
phone number or ID. The Gatekeeper matches the alias with a corresponding IP address and
routes the call to the requested endpoint.

Service Providers

H.323 endpoints that register with the Gatekeeper can also supply information relating to
the services they provide. The Gatekeeper identifies these services through prefixes.
Endpoints that supply service prefixes when they register to the Gatekeeper are service
providers. So that the Gatekeeper can identify these services, you have to set up a service
table with the required services.
Gateways and Gateway Hunting
Gateways provide services to LAN terminals in the form of outbound calls to terminals or
phones on the WAN. The Gateway registers with the Gatekeeper and informs the
Gatekeeper of the services it supports. When the Gatekeeper receives a service request that
is a call prefixed by one of the services supported by the Gateway, the Gatekeeper forwards
the call to the first available Gateway that supports the requested service. The Gatekeeper's
ability to search for an available Gateway is called Gateway Hunting.
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