Nortel Networks 1000 User Manual

Page 710

710

NT8D15 E and M Trunk card

Figure 240
Pad orientation

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Class of service is assigned in LD 14.

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Facility termination is selected (2-wire or 4-wire) in LD 14 (the 2-wire
setting provides 0.5 dB more loss in each direction of transmission for
echo control).

Note:

Facilities associated with the Nortel Networks Electronic

Switched Network (ESN) are recommended to be 4-wire for optimum
transmission; so the 4-wire setting is generally referred to as the
ESN setting. However, the 4-wire setting is not restricted to networks
using the ESN feature. Conversely, the 2-wire setting, often called
non-ESN, can be used on certain trunks in an ESN environment.

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Port-to-port connection loss is automatically set by software on the
basis of the port type selected in LD 16; only the port type is set by the
user.

The transmission properties of each trunk are characterized by the class of
service assigned in LD 14. Transmission properties can be Via Net Loss
(VNL) or not Via Net Loss (non-VNL).

The VNL class of service is assigned at the prompt CLS with the response
VNL. The non-VNL class of service is assigned at prompt CLS by selecting
either the Transmission Compensated (TRC) or Non-Transmission
Compensated (NTC) response.

Non-VNL trunks are assigned a TRC or NTC class of service to ensure
stability and minimize echo when connecting to long-haul trunks, such as
TIE trunks. The class of service determines the operation of the switchable
pads contained in each unit. They are assigned as follows:

Nortel Communication Server 1000

Circuit Card Reference

NN43001-311

02.06

Standard

27 August 2008