Nortel Networks 1000S - Manual (Page 39)

Configuration options Page 39 of 44
Communication Server 1000S Overview
— Requires its own Signaling Server.
— MG 1000B in remote branch offices enables local PSTN and 911
access.
— IP Phones are configured and managed centrally from the main
office.
— The MG 1000B is survivable in the event of a WAN failure.
— You can configure up to 400 users for survivability.
— You can use the Signaling Server virtual trunking to the central site
for system management purposes.
Routing to and from local branch offices
IP Phone users can be located at a branch office that is equipped with an
MG 1000B Core. Call routing to the local MG 1000B Core is important,
especially if toll charges are applicable to calls from the central Call Server
controlling the IP Phone. The administrator can configure digit manipulation
for IP Phones that are located near a branch office, in order to select a branch
office that provides local PSTN access.
Calls from the PSTN to users within the network can be routed using either
(a) the various ESN numbering plan configurations, or (b) the Network
Number Resolution feature, based upon the Vacant Number Routing feature.
This enables small sites, such as a branch office, to require minimal
configuration to route calls through other Call Servers or the Gatekeeper. See
Branch Office: Installation and Configuration (553-3001-214).