Which of the following description of the process for optimizing the line attenuation compensation anomaly is correct? (Multiple choice)
A . According to the user adjustment command, adjust the line attenuation of the OCh path to make the downstream light output reach the normal value.
B . The SCC board at the downstream site of the fault reports the alarm to the power detection unit (OA) of the first node through DCN communication, and reports the alarm to the SOM on the SC of the first node.
C . After receiving the alarm, the SOM obtains the OCh path corresponding to the alarm and adds it to the management path to be optimized.
D . The downstream power detection unit (OA) detects that the line attenuation deviation exceeds the threshold and reports the alarm to its own SCC board.
Answer: ACD