Nortel Networks NN43021-110 - Manual (Page 63)

Configuration options 63
communications network. The Call Server at the main office provides the
call processing for the IP Phones in both the main office and branch offices.
The MG 1000B Core provides call processing functionality to local digital
telephones and analog devices. The MG 1000B Core also provides digital
and analog trunk access to the local Public Switched Telephone Network
(PSTN).
The branch office connects to the main office over Virtual Trunks on an
enterprise IP network or a WAN. The main office transmits and controls IP
Phone calls and IP network connections. If the main office fails to function,
or if there is a network outage, the MG 1000B Small System Controller
(SSC) provides service to the telephones located in the branch office. This
enables the IP Phones to survive the outage between the branch office
and the main office.
A branch office can be created as a new hardware configuration, or by
converting an existing Small System to a branch office. The functionality
is the same in both configurations.
For more information on the Branch Office feature, see Branch Office
Installation and Commissioning (NN43001-314).
Geographic Redundancy
Geographic Redundancy enables a customer to duplicate the entire
redundant processing core of a CS 1000M SG or CS 1000M MG system at
a remote location, at any distance, over the customer WAN. The duplicate
core can then take over processing if the primary system fails for any
reason. Geographic Redundancy also offers automatic database replication
between main and standby systems to promote a smooth transition. When
this configuration is implemented, the customer enhances the disaster
recovery capability of the network and further secures ultra-high reliability.
Note: Geographic Redundancy capabilities only apply to IP elements,
for example, to IP Phones and Media Gateways. Geographic
Redundancy does not apply to TDM elements.
For more information on the Geographic Redundancy feature, see System
Redundancy Fundamentals (NN43001-507).
Nortel Communication Server 1000
Communication Server 1000M and Meridian 1 Large System Overview
NN43021-110 01.03 Standard
Release 5.0 18 February 2008
Copyright © 2003-2008, Nortel Networks
.