Nortel BCM 3.7, Manual

Page: 203 / 1004

Planning your telephony services 203
Programming Operations Guide
DID system
This setup allows you to assign a dedicated phone number to each telephone. The CO assigns a list
of available numbers for each DID (Direct Inward Dial) line. You can change your DN range to
match these numbers, or you can use target lines to match each number with a DN.
Figure 52 DID system
Incoming calls
1 DID trunks are assigned to be auto-answer.
Note: PRI and BRI lines are automatically set to auto-answer.
2 All telephones are assigned target lines.
3
A caller dials a system code and a DN. In the example shown above, it might be 769-4006.
4 The call comes into the trunk, which answers and forwards the call on the target line assigned
to that number.
5 The telephone assigned to that target line rings.
You can assign unanswered or busy telephones to Call Forward to a prime set, if you have a
designated attendant, or to a voice mail system.
CO DID line i.e. 769
with range of call
numbers (i.e. 4005 to
4020)
Target line mapped to
DN (4005)
Target line mapped to
a DN (4006)
Target line mapped to
DN (4007)
Target line mapped to
DN (4008)