Nortel BCM 3.7 Manual page 315

Table 52 Private network values
Private Network ID
(CDP/UDP networks)
* CDP and UDP private DN lengths are determined this way:
CDP: the system uses the telephone DN length
UDP: the system combines the private access code length + location code length + telephone DN length. When a call
comes in, the system recognizes the leading digits as a private call and removes (truncates) them, leaving the
telephone DN, which is recognized as the private DN length.
1-127
Configuring the public and private dialing plans
This is the unique number that identifies the system to the
Meridian PRI-MCDN network. Both end points must match
on a PRI-MCDN network.
On a VoIP trunking-MCDN network, this ID must be the
same on all nodes.
This number is supplied by the private network
administrator.
Refer also to "Configuring special IP trunking
interoperability" on page
Programming Operations Guide
545.
315