Stm-1 Loss Of Frame Alignment - Alcatel-Lucent 1643 AMS Operation Manual

Alarm messages

STM-1 Loss of frame alignment

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Alarm identifier
Information
Alarm category
ASAP
Alarm severity
(default setting)
Reporting state
(default setting)
Local indications
Cause
Actions
Note(s)
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365-312-803R7.2
Issue 4, May 2007
STM1cLOF
The position of the frame alignment bytes A1 and A2 in the Section Overhead
of the receive signal cannot be detected correctly. Thus, alignment to the
framing structure of the received signal is not possible, and as a result,
overhead and payload data cannot be extracted.
Transmission
sdhPRS
Prompt
Reported
The red fault LED is flashing.
Possible causes of the alarm are:
•
Unexpected signal structure in the receive signal (for example STM-4
instead of STM-1)
•
Dirty optical connector(s)
•
STM-1 not correctly formed in the upstream station
•
Equipment fault(s) in the upstream station
Check upstream external cabling and equipment.
In the downstream direction, AIS is inserted.
In the upstream direction, "Multiplex Section - Remote Defect Indicator"
(MS-RDI) is inserted.
Alcatel-Lucent - Proprietary
See notice on first page
1-169