Nortel Networks OPTera Metro 3500 - Manual (Page 159)

Operation, administration, and maintenance (OAM) features 2-121
Planning and Ordering Guide—Part 1 of 2 NTRN10AN Rel 12.1 Standard Iss 1 Apr 2004
The PSC-W, PSC-P, and PSD parameters are defined as follows:
• PSC-W—For a working line, PSC-W is the number of times that service
switched from the working line to the protection line, plus the number of
times that service switched back to the working line.
• PSC-P—For a protection line, PSC-P is the number of times that service
switched from the working line to the protection line, plus the number of
times service switched back to the working line.
• PSD—For a working line, PSD is the number of seconds that service was
carried on the protection line. For a protection line, PSD is the number of
seconds that the line was used to carry service. The PSD parameter is
applicable only if the protection scheme is revertive.
Note: You cannot set thresholds for the protection PM parameters.
Protection PM in a linear 1+1 configuration
Protection PM parameters are applicable to OC-3, OC-12, OC-48 and OC-192
facilities in a linear 1+1 configuration.
The working and the protection facilities in a linear 1+1 configuration are on
separate lines. Therefore, the PSC-P parameter on the working line and the
PSC-W parameter on the protection line are fixed at 0.
The linear 1+1 configuration is non-revertive. Therefore, the PSD parameter
for facilities in a linear 1+1 configuration is fixed at 0.
Protection PM in a BLSR configuration
Protection PM parameters are applicable to OC-48 and OC-192 facilities in a
BLSR configuration. Protection PM parameters increment on switching nodes
only and not on pass-through nodes.
Because each line in a BLSR configuration includes both working and
protection facilities, the PSC-P and the PSC-W parameters increment
independently on each line.
For the BLSR configuration, the PSD parameter increments only if the
protection switch is revertive. The PSD parameter is not applicable in the
following cases:
• revertive operation is disabled (by setting the wait-to-restore period to
infinite)
• a manual switch or a forced switch is activated
• In these two cases, the PSD parameter is fixed at 0.