Cisco ONS 15454 Troubleshooting Manual page 411

Chapter 2 Alarm Troubleshooting
For more information about the ML-Series Ethernet cards, refer to the Cisco ONS 15454 and
Note
Cisco ONS 15454 SDH Ethernet Card Software Feature and Configuration Guide.
2.7.356 SD (DS1, DS3)
A Signal Degrade (SD) condition for DS-1 or DS-3 occurs when the quality of an electrical signal on a
DS3XM-6, DS3XM-12, or DS3/EC1-48 card has exceeded the BER signal degrade threshold. Signal
degrade is defined by Telcordia as a soft failure condition. SD and signal fail (SF) both monitor the
incoming BER and are similar, but SD is triggered at a lower bit error rate than SF.
The BER threshold is user-provisionable and has a range for SD from 1E–9 dBm to 1E–5 dBm.
SD can be reported on electrical card ports that are In-Service and Normal (IS-NR); Out-of-Service and
Autonomous, Automatic In-Service (OOS-AU,AIS); or Out-of-Service and Management, Maintenance
(OOS-MA,MT), but not in the Out-of-Service and Management, Disabled (OOS-MA,DSBLD) service
state. The BER count increase associated with this alarm does not take an IS-NR port out of service, but
if it occurs on an AINS port, the alarm prevents the port from going into service.
The SD condition clears when the BER level falls to one-tenth of the threshold level that triggered the
condition. A BER increase is sometimes caused by a physical fiber problem such as a faulty fiber
connection, a bend in the fiber that exceeds the permitted bend radius, or a bad fiber splice. SD can also
be caused by repeated XC10G card switches that in turn can cause switching on the lines or paths.
Invisible laser radiation could be emitted from the end of the unterminated fiber cable or connector.
Warning
Do not stare into the beam directly with optical instruments. Viewing the laser output with certain
optical instruments (for example, eye loupes, magnifiers, and microscopes) within a distance of
100 mm could pose an eye hazard. Statement 1056
Warning Use of controls, adjustments, or performing procedures other than those specified could result in
hazardous radiation exposure. Statement 1057
Some levels of BER errors (such as 1E–9 dBm) take a long period to raise or clear, about 9,000 seconds,
Note
or 150 minutes. If the SD threshold is provisioned at 1E–9 dBm rate, the SD alarm needs at least one
and one-half hours to raise and then another period at least as long to clear.
The recommended test set for use on all SONET ONS electrical cards is the Omniber 718. For specific
Note
procedures to use the test set equipment, consult the manufacturer.
November 2009
Default Severity: Not Alarmed (NA), Non-Service-Affecting (NSA)
SONET Logical Objects: DS1, DS3
Cisco ONS 15454 Troubleshooting Guide, R8.5
2.7.356 SD (DS1, DS3)
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