58
D14049.07
March 2010
Grey Headline
(continued)
TANDBERG
VIDEO COMMUNICATION SERVER
ADMINISTRATOR GUIDE
Introduction
Overview and
status
System
configuration
VCS
configuration
Zones and
neighbors
Clustering and
peers
Call
processing
Bandwidth
control
Firewall
traversal
Appendices
Applications
Maintenance
Registration control
About alias registration
After the
authentication
process (if required) has been
completed, the endpoint will then attempt to register its alias(es)
with the VCS.
H.323
When registering, the H.323 endpoint presents the VCS with one
or more of the following:
•
one or more H.323 IDs
•
one or more E.164 aliases
•
one or more URIs
Users of other registered endpoints can then call the endpoint
by dialing any of these aliases.
You are recommended to register your H.323 endpoints
using a URI. This facilitates interworking between SIP
and H.323, as SIP endpoints register using a URI as
standard.
You are recommended to not use aliases that reveal
sensitive information. Due to the nature of H.323, call
setup information is exchanged in an unencrypted form.
SIP
When registering, the SIP endpoint presents the VCS with its
contact address (IP address) and logical address (Address of
Record). The logical address is considered to be its alias, and
will generally be in the form of a URI.
Attempts to register using an existing alias
An endpoint may attempt to register with the VCS using an alias that is already registered to the system. How this is managed
depends on how the VCS is configured and whether the endpoint is SIP or H.323.
H.323
An H.323 endpoint may attempt to register with the VCS using an alias that has already been registered on the VCS from another IP
address. The reasons for this could include:
•
two endpoints at different IP addresses are attempting to register using the same alias
•
a single endpoint has previously registered using a particular alias. The IP address allocated to the endpoint, or the port the
endpoint uses to communicate with the VCS, then changes, and the endpoint is attempting to re-register using the same alias.
You can determine how the VCS will behave in this situation by configuring the
Registration Conflict Mode
, using either:
•
VCS configuration > Protocols > H.323
You will be taken to the
H.323
page.
•
xConfiguration H323 Gatekeeper Registration ConflictMode
The options are:
Reject
: the registration from the new IP address will be rejected. This is useful if your priority is to prevent two users registering with
the same alias.
Overwrite
: the existing registration will be overwritten using the new IP address. This is useful if your network is such that endpoints
are often allocated new IP addresses, because it will prevent unwanted registration rejections.
The default is
Reject
.
SIP
A SIP endpoint will always be allowed to register using an alias that is already in use from another IP address. When a call is received
for this alias, all endpoints registered using that alias will be called simultaneously. This SIP feature is known as “forking”.
Blocking registrations
If you have
configured the VCS to use a Deny List
, from the
Registration details
page (
Status > Registrations > by Device
and click a
Name
; or
Status > Registrations > by Alias
and click an
Alias
; or
Status > Registrations > History
and click an
Alias
) you will have an
option to block the registration. This will add all the aliases used by that endpoint to the Deny List.
Registering aliases
