Lucent Technologies DDM-2000 OC-3, User & Service Manual

Page: 567 / 2536

363-206-285
Maintenance Description
Issue 3 June 2001 9-45
C-Bit 9
When the DS3 path PM C-bit option is selected, both near-end and far-end (far-
end block errors — FEBE) PM data are monitored and displayed.
The system provides counts of DS3 C-bit parity coding violations (CV-P), ES-P,
SES-P, and UAS-P incoming from both the DSX-3 and the fiber. The type of PM is
provisioned per DS3 service by a CIT command.
For C-bit PM, the DS3 service can be provisioned in violation monitor (VM) or
violation monitor and removal (VMR) modes. In VMR mode, the C-bit errors are
not corrected as in the P-bit option.
Quarter-hour and day registers are provided with provisionable TCAs. The TCAs
are provisionable on a per-shelf basis. SEFS counts are also provided.
DS3 Line 9
DS3 line parameters include line coding violations (CVL), errored seconds (ESL),
and severely errored seconds (SESL). DS3 line PM provides provisionable bit
error ratios (TCAs) for all DS3 line parameters. For CVL parameters, bit errors
can also be provisioned in ratios such as 10
-7
, 10
-8
and 10
-9
.
Optical Parameters 9
Performance Monitoring Enabling 9
Collection of optical parameters are initiated when a slot is equipped with an OLIU
circuit pack. Parameters continue to be available in reports and generate
appropriate TCAs until the OLIU is removed and the
update
command or the
UPD/INIT button is pressed.
Laser Bias Current 9
The laser bias current is monitored continuously to detect degraded performance
of the laser. A TCA is generated if the laser bias current exceeds a fixed threshold
of 1.5 times the nominal value. Laser bias current is monitored independently for
service and protection optical facilities.
Optical Transmit Power 9
The optical transmit power is monitored continuously to detect degraded
performance of the laser. Threshold-crossing alerts (TCAs) are generated if the
optical transmit power falls below fixed thresholds of
−
1 dB and
−
2 dB. Optical