Pad Switching - Nortel Meridian 1 Option 11C Compact Technical Reference Manual

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PAD switching

553-3121-100 Standard 2.0
Chapter 11 — NTMW07 Trunk/Line Card
The transmission properties of each trunk are characterized by the
class-of-service (COS) assigned in the Trunk Data Block (LD 14).
Transmission properties may be via net loss (VNL) or non via net loss
(non-VNL).
Non-VNL trunks are assigned either a Transmission Compensated (TRC) or
Non-Transmission Compensated (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:
• Transmission Compensated
— used for a two-wire non-VNL trunk facility with a loss of greater
than 2 dB for which impedance compensation is provided
— or used for a four-wire non-VNL facility
• Non-Transmission Compensated
— used for a two-wire non-VNL trunk facility with a loss of less than
2 dB
— or used when impedance compensation is not provided
Table 42 shows PAD settings and the resulting port-to-port loss for trunk
connections between the NTMW07 Trunk/Line Card and any other
Peripheral Equipment (PE) unit, denoted as Port B
In Meridian 1 Option 11C Compact systems, the insertion loss from PE ports
to PE ports is as follows.
September 1998