MPLS-TP Proactive Continuity and Connectivity Verification

The aim of this draft is to define an MPLS-TP OAM mechanism to meet the requirements for proactive Continuity Check and Connectivity Verification functionality as defined in [3]. Note: this version of the draft is focused on analyzing possible solutions and evaluating their pros&cons as well as issues. In the next version of the draft the solution to be standardized will be proposed using the analysis done in this version to motivate the selection.