This Recommendation specifies the interfaces for the MPLS Transport Profile (MPLS-TP) layer network, in particular the:encapsulation of MPLS-TP client signals into the MPLS-TP characteristic information that will be present on MPLS-TP NNI links in the transport network;encapsulation of MPLS-TP characteristic information into the MPLS-TP link frames that will be present on MPLS-TP NNI links in the transport network;MPLS-TP layer network within the transport network and associated MPLS-TP multiplexing;MPLS-TP nested connection monitoring per layer network level within the transport network;MPLS-TP OAM associated with nested connection monitoring in the transport network;encapsulation of MPLS-TP control plane information.