Polycom VS4000 User Manual

Integrators’ Reference Manual for ViewStation EX, ViewStation FX, and VS4000

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www.polycom.com

The addressing components of an H.323 dial plan are:

❑

Gatekeeper zone identifiers or prefixes

❑

Entity addressing

❑

Terminal aliases (include numeric and alphabetic aliases)

❑

System Services

❑

MCU service prefixes

❑

Gateway service prefixes

Each H.323 entity must have at least one network address (transport 
address). The network address uniquely identifies the H.323 entity 
on the network. It is typically a TCP/IP address. 

If the entity is a terminal, it may also have one or more alias 
addresses associated with it.

A zone is the collection of all terminals, gateways, and MCUs 
managed by a single gatekeeper. A zone may be independent of 
network topology, and may include multiple network segments 
which are connected by routers and other devices. 

When using multiple zones (multiple gatekeepers), zone identifiers 
must be used. Zone identifiers are analogous to area codes.

Specifying local zone prefixes enables the gatekeeper to resolve 
addresses sent by neighbor gatekeepers. The local zone prefix 
identifies this gatekeeper. Some gatekeepers do not strip prefixes 
before the address when sending out a request for address 
resolution. These addresses cannot be resolved without the local 
zone prefix. The local zone prefix needs to be removed from the 
dialed address in order to match the address to a registrant.