Nortel BCM 3.7, Manual

Page: 149 / 1004

Defining trunk module types and settings 149
Programming Operations Guide
Interface levels
The default Interface levels are the ISDN loss plan settings.
Check with your telecommunications service provider to determine if your Business
Communications Manager system is connected to a central office (CO) with digital network loss
treatment (ISDN I/F levels) or analog network loss treatment (PSTN I/F levels).
The ISDN setting requires digital access lines (DAL) that have digital network loss treatment. On
a DAL network, the PBX system administers the dB loss not than the CO. DALs may have ISDN
signaling or digital signaling (for example, T1). The loss plan follows the Draft TIA-464-C loss
plan, which uses a send loudness rating (SLR) of 8 dB. You must contact your service provider to
get DAL network loss treatment on a line with digital signaling.
The PSTN setting requires analog access lines (AAL) that have analog network loss treatment and
digital signaling. On an AAL(D) network, the CO administers the dB loss.
The loss plan follows the Draft TIA-464-C loss plan. The ISDN loss plan uses a send loudness
rating (SLR) of 8 dB and a receive loudness rating (RLR) of 2 dB. The PSTN loss plan uses an
SLR of 11 dB and an RLR of -3 dB. If you choose the wrong setting, the voice signal can be too
loud or too soft.
Internal CSU
Internal CSU allows you to turn the internal T1 channel service unit on or off. The channel service
unit gathers performance statistics for your T1 lines or PRI with public interface. Contact your
service provider for the correct settings.
Note: You must disable the DTM before you can change this setting. See “Disabling/enabling a
single module” on page 159 for details.
You can view the performance statistics for your T1 lines in Maintenance under the CSU stats
heading. Before you set the internal CSU to off, you must ensure there is an external CSU
connected to your T1 lines.
DSX1 build 000-100, 100-200,
200-300, 300-400,
400-500, 500-600,
or 600-700 feet Set the distance between Business Communications Manager
and an external channel service unit. This setting only appears
when the Internal CSU is set to Off. Contact your service provider
for the proper settings.
Line coding B8ZS or AMI Define the encoding signals on a T1 line. Select the standard
used by your T1 service provider. Contact your T1 service
provider for the proper setting.
Table 13 TI parameters (Continued)
Attribute Value Description