Which of the following description of the DM12 board are correct? (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).

The 40 Gbit/s and 100 Git/s coherent systems do not require dispersion compensation because the coherent board has a large dispersion tolerance. NG WDM does not support non-coherent networks and coherent networks for hybrid transmission.

The OCh path is created using the single station method. After the creation is completed, the 0ch path is not searched. Which are the possible reasons? (Multiple choice)

The following description of the PM_BIP8 related alarm, which is correct?