About Registrations; Finding A Vcs With Which To Register; Registrations On A Vcs Expressway - Cisco TelePresence Administrator's Manual

Registration control

About registrations

For an endpoint to use the VCS as its H.323 gatekeeper or SIP registrar, the endpoint must first register with
the VCS. The VCS can be configured to control which devices are allowed to register with it by using the
following mechanisms:
a device authentication
n
a registration restriction policy
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specify which aliases can and cannot register with the VCS
restrictions based on IP addresses and subnet ranges through the specification of subzone membership
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rules and subzone registration policies
You can use these mechanisms together. For example, you can use authentication to verify an endpoint's
identity from a corporate directory, and registration restriction to control which of those authenticated
endpoints may register with a particular VCS.
You can also control some protocol-specific behavior, including:
the Registration conflict mode and Auto discover settings for
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the SIP registration proxy mode for
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For specific information about how registrations are managed across peers in a cluster, see the
registrations across peers [p.166]
In a Unified Communications
CM. In this scenario, the VCS provides secure firewall traversal and line-side support for Unified CM
registrations. When configuring domains, you must select the system - either Unified CM or VCS to provide
registration services for each domain.

Finding a 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

Registrations on a VCS Expressway

If a traversal-enabled endpoint registers directly with a VCS Expressway, the VCS Expressway will provide
the same services to that endpoint as a VCS Control, with the addition of firewall traversal. Traversal-
enabled endpoints include all Cisco TelePresence Expressway™ endpoints and third-party endpoints which
support the ITU H.460.18 and H.460.19 standards.
Endpoints that are not traversal-enabled can still register with a VCS Expressway, but they may not be able
to make or receive calls through the firewall successfully. This will depend on a number of factors:
whether the endpoint is using SIP or H.323
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the endpoint's position in relation to the firewall
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whether there is a NAT in use
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whether the endpoint is using a public IP address
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Cisco VCS Administrator Guide (X8.1.1)
process based on the username and password supplied by the endpoint
that uses either Allow Lists or Deny Lists
SIP registrations
section.
deployment, endpoint registration for SIP devices may be provided by Unified
or an external policy service to
H.323 registrations
SIP and H.323.
About registrations
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