Nortel Remote Gateway 50 Configuration Manual page 129

Alternative Call Routing for Network Bandwidth Management
When there is insufficient bandwidth for a station-to-station call, the
Alternative Call Routing for NBWM feature uses a trunk for a call which
would not normally use a trunk.
Prior to the introduction of the Alternative Call Routing for NBWM feature,
there was no alternate routing mechanism for the following types of
station-to-station calls:
• Branch office calls to or from the main office
• Branch office calls to or from another branch office controlled by the
same main office
Note: The term "branch office" refers to Media Gateway 1000B
(MG1000B) and Survivable Remote Gateway (SRG) systems in this
document.
This feature enables alternate routing to occur for branch office users
registered to the main office, when they place inter-zone, station-to-station
calls to main office stations or branch office stations.
The Alternative Call Routing for NBWM feature can be triggered by
operation of either of the following features:
• NBWM
• Adaptive Network Bandwidth Management
For more information on Network Bandwidth Management and Adaptive
Network Bandwidth Management, refer to IP Peer Networking: Installation
and Configuration (553-3001-213).
The Alternative Call Routing for NBWM feature can be implemented to
operate in one of the following two ways:
• Bandwidth insufficiency: Alternately routes station-to-station IP
network calls that encounter lack of bandwidth or poor QoS in the
originating or terminating zone as the calls are being established
• All Calls: Alternately routes station-to-station IP network calls,
regardless of available bandwidth
Main Office Configuration for Survivable Remote Gateway 50
Page 129 of 258
Configuration Guide