Protocols; About H.323; Using The Vcs As An H.323 Gatekeeper; H.323 Endpoint Registration - Cisco TelePresence Video Communication Server Administrator's Manual

Protocols

This section provides information about the pages that appear under the
Protocols menu.
It includes the following information:
an overview of H.323
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an overview of SIP and the
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how to configure the VCS to act as a
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About H.323

The VCS supports the H.323 protocol: it is an H.323 gatekeeper.
It will also provide interworking
enable endpoints that only support one of these protocols to call each other. In order to support H.323,
the H.323 mode must be enabled.

Using the VCS as an H.323 gatekeeper

As an H.323 gatekeeper, the VCS accepts registrations from H.323 endpoints and provides call
control functions such as address translation and admission control.
To enable the VCS as an H.323 Gatekeeper, you must ensure that H.323 mode is set to On
configuration > Protocols >
Note that this is the default setting, so the VCS will work as an H.323 gatekeeper "out of the box",
without any other special configuration.

H.323 endpoint registration

H.323 endpoints in your network must register with the VCS in order to use it as their gatekeeper.
There are two ways an H.323 endpoint can locate a VCS with which to register: manually or
automatically. The option is configured on the endpoint itself under the Gatekeeper Discovery setting
(consult your endpoint manual for how to access this setting).
If the mode is set to automatic, the endpoint will try to register with any VCS it can find. It does this
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by sending out a Gatekeeper Discovery Request, to which eligible VCSs will respond.
If the mode is set to manual, you must specify the IP address of the VCS with which you want your
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endpoint to register, and the endpoint will attempt to register with that VCS only.
Preventing automatic H.323 registrations
You can prevent H.323 endpoints being able to register automatically with the VCS by disabling Auto
Discovery on the VCS (VCS configuration > Protocols >

About SIP

The VCS supports the SIP protocol. It acts as a SIP registrar, SIP proxy and as a SIP Presence
Server.
The VCS can provide interworking between SIP and H.323, translating between the two protocols to
enable endpoints that only support one of these protocols to call each other.
To support SIP:
Cisco VCS Administrator Guide (X6.1)
and the H.323 configuration options
SIP configuration options
SIP to H.323 gateway
between H.323 and SIP, translating between the two protocols to
H.323).
VCS configuration >
available on the VCS
available on the VCS
H.323).
Protocols
(VCS
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