Nortel BCM 3.7, Manual

Page: 535 / 1004

Understanding MCDN network features 535
Programming Operations Guide
Trunk Route Optimization
TRO finds the most direct route through the network to send a call between nodes. This function
occurs during the initial alerting phase of a call.
Business Communications Manager configurations:
• Under Network Services, MCDN , set TRO to Y(yes).
• Configure call routing for all optimal routes.
• Configure call forward (All Calls, No Answer, Busy) or Selective Line Redirection to use the
optimal routes.
This feature avoids the following situation: A call originating from a Business Communications
Manager system may be networked to a Meridian system, which, in turn, is networked to another
Meridian system, which is the destination for the call. If the call routes through the first Meridian
(M1) to reach the second Meridian (M2), two trunks are required for the call. An optimal choice is
a straight connection to M2. This finds these connections and overrides the less-efficient setup.
The following figure shows two call paths. The first route, through the Meridian, demonstrates
how a call might route if TRO is not active. The second route, that bypasses the Meridian,
demonstrates how TRO selects the optimum routing for a call.
Figure 186 Call paths with and without TRO
If you are using a Meridian 1 system as part of the network, you need the following programming
for each system:
M1 TRO set to yes for BCM route:
LD 16
TYPE: RDB
Cust: xx
Rout: 0-511
TRO: Yes
Business
Communications
Manager
Meridian 1
Telephone A
Telephone B
Telephone C
Forwarded call (no TRO)
Original call (no TRO)
Meridian 1
PRI SL-1
PRI SL-1
PRI SL-1
Call path with TRO