A system is configured with SOM, and only the optical power information is displayed in the query spectrum analysis data, and the OSNR is displayed as " —". At this time, the OSNR is abnormal. What are the possible reasons? (Multiple choice)
A . The OMS segment is incorrectly configured or the board is not present in the OMS segment.
B . A board optical cross exists in the Och path or Och is not created
C . transceiver OMCA/MCA4/MCA8 board scanning spectrometer inconsistency
D . Communication between network elements is abnormal
E . After the networking changes, the SOM function is not reconfigured
Answer: ABCDE