Nortel Networks Remote Gateway 50 - Manual (Page 170)

Page 170 of 258 Dialing Plan configuration
553-3001-207 Standard 2.00 January 2006
Routing calls
SRG user call to an SRG PSTN
The SRG user telephone is registered at the main office. The SRG user
telephones are physically located at the branch office, so routing of local
PSTN calls back to the branch office is essential, even if they are registered
with the main office.
Branch office behavior of the SRG user telephones at the main office is
configured by setting branch office zone characteristics through LD 117 at
the main office.
SRG PSTN to an SRG telephone (DID call)
If the DN is valid and can terminate, call termination at the branch office is
treated differently for IP Phones and non-IP Phones, as follows:
• IP Phones — If the telephone is registered to the SRG (Local Mode), the
call is terminated locally. If the telephone is not registered to the SRG
(Normal Mode), the call is routed through a Virtual Trunk to the main
office.
• Non-IP Phones — Calls are terminated locally (within the branch office).
H.323 zones
In an H.323 network, each NRS controls one H.323 zone. Each zone can
consist of many H.323 endpoints. If a call terminates beyond the call
originator’s own zone, the NRS (H.323 Gatekeeper) of the called party’s zone
provides the endpoint information to set up the connection.
It is possible to divide a system into several zones. It is also possible to divide
a customer within a system into different zones. It is more common to assign
one zone to one system and one customer.