Nortel Networks 1000 - Manual (Page 710)

710 NT8D15 E and M Trunk card
Figure 240
Pad orientation
• Class of service is assigned in LD 14.
• 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.
•
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
Copyright © 2003-2008 Nortel Networks
.