TANDBERG Border Controller User Guide
Page 45 of 118
10.
URI Dialing
10.1.
About URI Dialing
If an alias is not located in the Border Controller's list of registrations, it may attempt to find an
authoritative Gatekeeper through the DNS system.
URI dialing makes it easier for endpoints registered with different Gatekeepers or Border Controllers to
call each other. Without URI dialing, you need to neighbor all the systems to each other. This does not
scale well as the number of systems grows. It is also inconvenient for making one-off calls to endpoints
registered with previously unknown systems.
Using URI dialing, you call using an H.323 URI which looks like an email address (e.g.
[email protected]). The destination Gatekeeper is found from the domain name -- the part after
the @ -- in the same way that an email server is found.
10.2.
Making a Call Using URI Dialing
10.2.1.
Enabling URI dialing
To enable or disable URI dialing using the command line interface, issue the following command:
xConfiguration Gatekeeper DNSResolution Mode: <On/Off>
To enable or disable URI dialing using the web interface, navigate to
Border Controller Configuration
>
Gatekeeper
and tick or clear the
Allow DNS resolution
checkbox.
10.2.2.
Configuring DNS server(s)
If URI dialing is enabled, you will also need to configure at least one DNS server for the systems to query.
For resilience, you can specify up to five DNS servers.
To do this, either issue the following command:
xConfiguration IP DNS Server 1 Address: <address>
or navigate to
System Configuration
>
IP
and under the
DNS
section, enter the IP address(es) of the DNS
server(s) you wish to use (see Figure 18).
Note:
If you want others to be able to reach you using URI dialing, add a record to your DNS
information as described in Appendix A
10.2.3.
Configuring the domain name
We recommend that endpoints register with a full URI (e.g. [email protected]).
However, your dial plan may be set up such that endpoints register with the Border Controller without
their domain name (e.g. firstname.lastname). In this case, the Border Controller needs to match an
incoming request for [email protected] to a registration for firstname.lastname. To do
this, it must be configured with the name of the domain to which its endpoints belong.
To configure the domain name, either issue the following command:
xConfiguration Gatekeeper LocalDomain DomainName: <name>
or navigate to
Border Controller Configuration
>
Gatekeeper
and in the
Local Domain
section in the
Domain name
field, enter the domain name.
The same local domain name should be set on both the Gatekeeper and the Border Controller. Any
Alternates should also have the same local domain name.
10.2.4.
URI dialing and firewall traversal
If URI dialing is being used in conjunction with firewall traversal, DNS Resolution should be enabled only
on the Border Controller and any Gatekeepers on the public network. Gatekeepers behind the firewall
should not have DNS resolution enabled.
