Whether SS bit mismatch in AU pointers during WDM product interconnection causes an AU_LOP alarm

1. OTU boards on WDM equipment, except OCU, transparently transmit SS bits without detection.
2. OCU boards process SS bits. The SS bit should be set to 10. When the SS bit is set to 00, 01, or 11, AU_AIS is inserted and services are interrupted. In this scenario, no alarm is reported on the board (because the AU_AIS alarm is not detected on the WDM side of the board.)
During a test, the Agilent OmniBer 817 meter is used to transmit STM-16 data. When the Payload option is Framed or Structed and the column in the overhead setup is set to ALL, you can change the H1 SS bit. When the SS bit is set to 00, 01, or 11, an AU_AIS, PDH, or LOF alarm is reported. When it is set to 10, no abnormality occurs.
This issue is related to the chip processing mode. OCU boards use the same chip and therefore have the issue.

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