Summary

Recommendation ITU-T G.873.1 defines the automatic protection switching (APS) protocol and protection switching operation for the linear protection schemes for the optical transport network at the optical channel data unit k (ODUk) level. Protection schemes considered in this Recommendation are:

����������� ODUk subnetwork connection protection with inherent monitoring (1+1, 1:n);

����������� ODUk subnetwork connection protection with non-intrusive monitoring (1+1);

����������� ODUk subnetwork connection protection with sublayer monitoring (1+1, 1:n).

����������� ODUk compound link subnetwork connection group protection with inherent monitoring (1+1, 1:1).

In addition, client-related protection architectures are described.