The Branch Office feature is implemented on a Media Gateway 1000B
(MG 1000B) platform. The MG 1000B platform includes an MG 1000B
Core connected to an IP PBX at the main office over a LAN or a WAN. This
configuration enables a secondary location to centralize the call processing
of its IP-based communication network. The Call Server at the main office
provides the call processing for the IP Phones in both the main office and
Branch Office locations. 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 MG 1000B platform connects to the main office over Virtual Trunks on
a LAN/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 Media Gateway Controller (MGC) card in the MG
1000B Core provides service to the telephones located at the Branch Office
location. This enables the IP Phones to survive the outage between the
Branch Office and the main office.

Currently, MG 1000B Branch Office is small system based; which is still
supported in CS 1000 Release 5.0. In addition, changes are made to
allow large system based branch offices. Branch Office configurations
supported in CS 1000 Release 5.0, and are not changed with the CP PM
(Call Processor Pentium Mobile). Additionally, the CP PM adds the ability

Nortel Communication Server 1000

Branch Office Installation and Commissioning

NN43001-314

01.02

Standard

Release 5.0

20 June 2007