Juniper Networks Cisco Systems RAD Data Communications This document describes VCCV2, a new version of Virtual Circuit Connectivity Verification (VCCV), the pseudowire OAM mechanism. This new version is backwards compatible with VCCV for MPLS PWs for modes that the versions share, although the Router Alert (RA) CV type is not supported by VCCV2. Furthermore, this document collects the complete description of VCCV2 into a single specification.