116
D14049.05
February 2009
Grey Headline
(continued)
TANDBERG
VIDEO COMMUNICATIONS SERVER
ADMINISTRATOR GUIDE
Introduction
Getting started
Overview and
status
System
configuration
VCS
configuration
Zones and
neighbors
Call
processing
Bandwidth
control
Firewall
traversal
Appendices
Applications
Maintenance
IP dialing
Overview
Although the VCS supports dialing by IP
address, it is sometimes undesirable for a
VCS to be allowed to place a call directly to an
IP address that is not local. Instead, you may
want a neighbor to place the call on behalf of
the VCS, or not allow such calls at all. The VCS
allows you to configure how it will behave when
receiving a call for an IP address that is not
local. This is done from the
Calls to Unknown
IP addresses
setting.
To configure this setting from the web interface,
go to the
Calls
page (
VCS configuration > Calls
).
To configure this setting from the CLI:
xConfiguration Call Services
•
CallsToUnknownIPAddresse
s
About unknown IP addresses
The VCS considers an IP address to be "known"
if it either:
is the IP address of a locally registered
•
endpoint
falls within the IP address range of one of the
•
subzones configured on the VCS.
Calls to these IP addresses are not affected by
the
Calls to Unknown IP addresses
setting - the
VCS will always attempt to place the call.
All other IP addresses are considered to be
"unknown" and will be handled by the VCS
according to its
Calls to Unknown IP addresses
setting.
Configuration
The options for the
Calls to Unknown
IP addresses
setting are:
Direct
The VCS will attempt to place the call directly to
the unknown IP address without querying any
neighbors.
Indirect
The VCS will forward the search request to its
neighbors in accordance with its normal search
process, i.e. any zones with an Always Match
will be queried in order of priority. If a match is
found and the neighbor’s configuration allows it
to connect a call to that IP address, the VCS will
pass the call to that neighbor for completion.
Off
The VCS will not attempt to place the call, either
directly or to any of its neighbors.
If the IP address either belongs to a
locally registered endpoint, or falls within
the IP address range of one of the
subzones configured on the VCS, the VCS will
always attempt to place the call regardless of
the
Calls to Unknown IP addresses
setting .
Recommended configuration for firewall
traversal
When the VCS Expressway is neighbored with
an VCS Control for firewall traversal, you should
typically set
Calls to unknown IP addresses
to
Indirect
on the VCS Control and
Direct
on
the VCS Expressway. When a caller inside the
firewall attempts to place a call to an IP address
outside the firewall, it will be routed as follows:
The call will go from the endpoint to the VCS
1.
Control with which it is registered.
Since the IP address being called is not
2.
registered to that VCS, and its
Calls to
unknown IP addresses
setting is
Indirect
, the
VCS will not place the call directly. Instead,
it will query its neighbor VCS Expressway to
see if that system is able to place the call on
the VCS Control’s behalf.
The VCS Expressway receives the call and
3.
since its
Calls to unknown IP addresses
setting is
Direct
, it will make the call directly
to the called IP address.
An unregistered endpoint is any device that is
not registered with an H.323 gatekeeper or SIP
Registrar (e.g. VCS, gatekeeper or TANDBERG
Border Controller). Although most calls are
made between endpoints that are registered
with such systems, it is sometimes necessary
to place a call to an unregistered endpoint.
There are two ways to call to an unregistered
endpoint:
by dialing its URI. This requires that the
•
local VCS has been configured to support
URI dialing, and that a DNS record exists for
that URI that resolves to the unregistered
endpoint's IP address.
by dialing its IP address.
•
The remainder of this section describes how
the VCS can be configured to handle calls
placed by dialing an endpoint's IP address.
Calls to unknown IP addresses
About unregistered endpoints
