This Recommendation defines the automatic protection switching (APS) protocol and linear protection switching mechanisms for point-to-point VLAN-based ETH subnetwork connection (SNC) in Ethernet transport networks. All other protection schemes including point-to-multipoint and multipoint-to-multipoint are for further study. Linear 1+1 and 1:1 protection switching architectures with unidirectional and bidirectional switching are defined in this version of the Recommendation. The APS protocol and protection switching operation for all other Ethernet network architectures (e.g.@ ring@ mesh) are for further study.