Regarding the electrical layer protection ODUk SNCP and branch SNCP, which one is different in the following description

The clock ID can solve the problem of timing loops that may occur. In the following networking, in order to completely solve the clock loop, how many clock IDs need to be set?

Discrete services are cross-connections with no path formed on the network management. Since no path is formed, it is a junk service and can be deleted directly.

What are the TDM circuit simulation encapsulation protocols? (multiple choice)

The GXCS single board of the OptiX OSN3500 equipment is upgraded to SXCS. In the case of active/standby configuration, the business will be interrupted during the upgrade process.