TANDBERG Gatekeeper - Manual (Page 41)

TANDBERG Gatekeeper User Guide
Page 41 of 105
9. URI Dialing
9.1. About URI Dialing
If an alias is not located in the Gatekeeper'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. The destination
Gatekeeper is found from the domain name -- the part after the @ -- in the same way that an email
server is found.
9.2. Making a Call Using URI Dialing
9.2.1. Enabling URI dialing
To enable or disable URI dialing using the command line interface, issue the following command:
xConfiguration Gatekeeper DNSResolution Mode:
To enable or disable URI dialing using the web interface, navigate to Gatekeeper Configuration >
Gatekeeper and tick or clear the Allow DNS resolution checkbox.
9.2.2. 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:
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
9.2.3. Configuring the domain name
Endpoints will typically register with the Gatekeeper without their domain name. The Gatekeeper needs
to match an incoming request for [email protected] to a registration for fred. 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:
or navigate to Gatekeeper 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.
9.2.4. 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.