Nortel BCM 3.7, Manual

Page: 332 / 1004

332 Configuring call routing
N0008589 3.3
Figure 98 Call Routing headings
Call routing decides what path an outgoing call takes using the digits that are dialed. It is
sometimes called Automatic Route Selection (ARS).
When you select an internal line and dial, the system checks the numbers you enter against the
routing tables. If the number you dial starts with a destination code, the system uses the line pool
and dials out digits specified by the route assigned to that destination code, and then dials the rest
of the number that you dialed.
Routing service replaces a number of manual tasks, including:
• entering a line pool code
• dialing an access code for a long distance carrier
• deciding which line pool to use according to the time and day
You can set up routing to take advantage of any leased or discounted routes using information
supplied by the customer. The system cannot tell what lines are cheaper to use.
For Call by Call service selection (PRI only), the installer defines destination codes for various call
types over PRI lines (for example, Foreign Exchange, Tie Trunk, or OUTWATS). The user dials a
number using the intercom button without entering any special information. For more information
see
“Provisioning for Call by Call limits with PRI” on page 352 .
Using routing to create a coordinated dialing plan is explained in “Configuring the public and
private dialing plans” on page 312 .
Warning: Plan your routing service before you do any programming.
Routing affects every call placed in the system and must be carefully planned to avoid
conflicts and gaps in the programming. Use tables to design routes and destination codes,
then check for potential problems before you start programming. It also saves you time
when all the settings are written out in front of you.
Call Routing
Routes
Route 000
External #
Use pool
Destination Codes
xx
Schedules