Neighbor Gatekeepers - TANDBERG N3 User Manual

TANDBERG Gatekeeper User Manual
NOTE
Automatic discovery is a function that allows the Gatekeeper to reply to multicast Gatekeeper
discovery messages from the endpoint.
NOTE
If you have problems registering the endpoint, try turning on automatic discovery. Some
endpoints require automatic registration to be enabled.
NOTE
When URI dialing is used to discover an endpoint, the URI used is based on either the H.323
ID or the E.164 alias that the endpoint registered with. The local domain is then added to this.
See section 3.9, URI Dialing for more details

3.3 Neighbor Gatekeepers

You may configure several Gatekeepers to work together, each taking responsibility for part
of the endpoint community. You will typically want to do this for separate geographical regions
or organizational entities. You may create a list of up to 100 neighbor Gatekeepers. Each of
these may be assigned a prefix, similar to an area code in telephony terms. All endpoints
which register with that Gatekeeper are assigned the same number prefix. They are referred
to as being in the Gatekeeper's zone. When one Gatekeeper needs to query another for a
particular number, it can consult its own prefix list, find the appropriate Gatekeeper and issue
the query.
The figure below shows an example with two zones, zone A with local prefix 54 and zone B
with local prefix 65. A also has B configured as its neighbor.
This means that a system in zone A can call a system in zone B. If terminal 1 wants to dial
terminal 3 it can do so by prefixing the number of terminal 3 with the zone prefix of zone B;
the number to dial will then be 65331.
The TANDBERG Gatekeeper also supports prefixless zones. If none of the prefix zones
provide a match for a dialed number, all of the prefixless zones will be queried.
In the example above, if Gatekeeper A had configured Gatekeeper B as a prefixless zone,
Terminal 1 could call Terminal 3 by dialing 331. Gatekeeper A will not recognize 331 as a
registered alias and because of this "forward" the request to the Gatekeeper in zone B.
Zones also play an important role in helping you to control the amount of traffic on your
network. See section 3.6, Bandwidth Control for details on this.
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