Which of the following technologies is the main difference between an open DWDM system and an integrated DWDM system?

Which of the following is the data that needs to be collected and saved in the event of a failure? (Multiple Choice)

Which of the following are not part of the 400G originating modulation technology?

In a typical chained NG WDM network (such as A -> B -> C, A, B, and C are three sites), it is found that the official telephone number between the stations is not available during the commissioning. What are the possible reasons? (Multiple choice)

For the relay type OTU, the alarms of all SM segments are terminated at the local station and are not transmitted downstream (except for OTUkLOF to insert ODUk_PI_AIS downstream). Other alarms continue to be transmitted to the downstream station and reported on the WDM side of the OTU (except for R_LOS to insert ODUK_PM_AIS to the downstream site).