Finding A Cisco Vcs With Which To Register; Sip; H.323; Preventing Automatic Registrations - Cisco TelePresence Administrator's Manual

Grey Headline (continued)
Registration control

Finding a Cisco VCS with which to register

Before an endpoint can register with a VCS, it must determine which VCS it can or should be
registering with. This setting is configured on the endpoint, and the process is different for SIP and

H.323.

SIP

SIP endpoints must find a SIP Registrar with which to register. The SIP registrar maintains a record
of the endpoint's details against the endpoint's Address of Record (AOR). When a call is received for
that AOR, the SIP registrar refers to the record in order to find the endpoint to which it corresponds.
(Note that the same AOR can be used by more than one SIP endpoint at the same time.)
The SIP registrar will only accept registrations for domains for which it is authoritative.
There are two ways a SIP endpoint can locate a registrar with which to register: manually or
automatically. The option is configured on the endpoint itself under the SIP Server Discovery option
(consult your endpoint user guide for how to access this setting; it may also be referred to as Proxy
Discovery).
•
If the Server Discovery mode is set to automatic, the endpoint will send a REGISTER message to
its SIP Server. This will be forwarded (via DNS if necessary) to the registrar that is authoritative
for the domain with which the endpoint is attempting to register. For example, if an endpoint is
attempting to register with a URI of john.smith@example.com, the request will be sent to the
registrar authoritative for the domain example.com.
•
If the Server Discovery mode is set to manual, the user must specify the IP address or FQDN of
the registrar with which they wish to register, and the endpoint will attempt to register with that
registrar only.
The VCS is a SIP Server for endpoints in its local zone, and can also act as a SIP registrar.
•
If the VCS is acting as the endpoint's SIP Server and SIP registrar, when the registration request
is received from the endpoint it will be accepted by the VCS and the endpoint will be registered
and able to receive inbound calls. See the
more information.
•
If the VCS is acting as the endpoint's SIP server but is not a SIP registrar, it will proxy the
registration request. See the Proxying registration requests
Overview and System
Introduction
status configuration
D14049.08
November 2010
Using the Cisco VCS as a SIP registrar section for
section for more information.
Cisco VCS Zones and Clustering and
configuration neighbors
Registration overview
H.323
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 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 wish
your endpoint to register, and the endpoint will attempt to register with that VCS only.

Preventing automatic registrations

You can prevent H.323 endpoints being able to register automatically with the VCS by disabling Auto
Discovery on the VCS. This setting is accessed using:
•
VCS configuration > Protocols > H.323.
You will be taken to the H.323 page.
xConfiguration H323 Gatekeeper AutoDiscovery
•
The Auto Discovery setting determines whether the VCS responds to the Gatekeeper Discovery
requests sent out by endpoints.
The options are as follows:
On: the VCS will respond to Gatekeeper discovery requests.
Off: the VCS will reject Gatekeeper discovery requests. H.323 endpoints will be able to register with
the VCS only if their Gatekeeper Discovery setting is Manual and they have entered the IP address
of the VCS.
Call Bandwidth
peers processing control
54
CISCO TELEPRESENCE VIDEO COMMUNICATION SERVER
Firewall
Applications Maintenance
traversal
ADMINISTRATOR GUIDE
Appendices