Summary

This ITU-T Recommendation defines maintenance thresholds and procedures for recovery mechanisms of international SDH VC trails (paths), multiplex sections (MSs) and subnetwork connections (SNCs), in case of failure, degradation, maintenance activities (e.g. planned outages).

This Recommendation deals with protection and restoration including return to original configuration. The internal protection capabilities of network element (NE) hardware are outside the scope of this Recommendation.

Maintenance thresholds and procedures given in this Recommendation are only used for protection and restoration of VCs trails (path), multiplex sections and subnetwork connections (SNCs)^[1].