Monitoring sections of PM and TCM overheads in OTN overheads


The SM, PM, and TCM overheads are generated at the source node and terminated at the sink node. The corresponding boards at the source and sink nodes monitor the signals and report the performance of the signals.
The SM overheads need to be terminated and then regenerated at all the nodes that have the 3R functions. That is, all the boards that support the OTN interface must process the SM overheads.
The PM overheads are terminated at the sink node of a channel.
The TCM overheads can be terminated at a selective sink node based on the actual situation. The TCM overheads have six levels and three allocation modes (cascaded, nested, or overlapped), which can be determined flexibly as required.

Other related questions:
OTN overheads
The OTN optical-layer overheads include OTS, OMS, and OCh overheads and are transmitted through the OSC. OTN electrical-layer overheads include OPUk, ODUk, OTUk overheads, and the frame alignment overheads.

Whether LMP uses OTN overheads or DCC overheads
LMP stands for Link Management Protocol. For optical-layer ASON services, LMP uses the DCC bytes of the OSC channels. For electrical-layer ASON services, LMP uses OTN overheads.

Difference between the operation mode and transparent mode in processing overheads
The operation mode and transparent mode differ in the generation of TCM overheads. To be specific, TCM overheads are re-generated in operation mode but not re-generated in transparent mode.

Difference between SNC/N and SNC/S in the case of TCM monitoring
For TCM monitoring, SNC/N and SNC/S differ in termination and modification of overheads. SNC/N monitors PM and TCM sections, while SNC/S monitors only the TCM section. Moreover, SNC/S can isolate external faults to avoid protection switching triggered by external faults.

Whether PM non-intrusive monitoring needs to be enabled for SNC/N services
Yes, PM non-intrusive monitoring needs to be enabled for SNC/N services. This configuration is automatically completed on the NMS and no manual operation is required in a version later than V100R006C01.

If you have more questions, you can seek help from following ways:
To iKnow To Live Chat
Scroll to top