The NG WDM two-dimensional ROADM site can use the WSMD9 single board, and its signal flow is an optical signal that is connected to the main optical channel from the "IN" optical port. The RDU (ROADM Demix Unit) optical module broadcasts nine identical optical signals, which are output from the "DM1~DM8" and "ECPO" optical ports respectively. One of the signals is localized by the splitter board, and the other eight signals are dispatched to the other eight directions. Each wave of the main optical channel is connected from the "EXPI" optical port. The multiplexed or single-wave optical signal that needs to be inserted locally is input through the "AM1"~"AM8" optical port.

The basic principles of STP device fault location are? (Multiple choice)

When you delete a discrete service, you can first activate it. At this time, you can view the alarm. If there is no alarm such as PS or TU-AIS, it is a garbage service. If there is an alarm, the analysis is incorrect. You need to activate it immediately.

Before creating an optical cross-connection, you need to manually configure the corresponding port of the corresponding board as a boundary port, for example, the line-side port of the FIU board between two sites.

Which of the following is a part of the optical layer in the OTN frame structure? (Multiple Choice)