Relationship between the OPUk_PLM alarm and ODUk_PM_UAS performance

According to the G.8021 protocol, near-end alarms are associated with bit error performance. Near-end alarms include OCh LOS, OTUk LOF, OTUk AIS, OTUk TIM, ODUk OCI, ODUk AIS, ODUk LCK, ODUk TIM, and OPUk PLM.
The generation conditions of the severely errored second (SES) are as follows: When there are no less than 30% bit errors or at least one defective second, a near-end alarm will cause a near-end SES. The SES is converted to a UAS performance after lasting 10s.
Therefore, an OPUk PLM alarm is a defect that can trigger an SES. That is, if the PM itself has no bit errors but the PT values to-be-received are inconsistent with those that are actually received, an ODUk_PM_UAS performance occurs.
It cannot be simply inferred that the ODUk UAS causes the OPUK_PLM alarm just because the ODUk layer is higher than the OPUk layer.

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