VCCV ping is used to check the connectivity (in-band) of a VLL. It checks that the destination (target) PE is the egress point for the Layer 2 FEC. It provides a cross-check between the data plane and the control plane. It is in-band, meaning that the VCCV ping message is sent using the same encapsulation and along the same path as user packets in that VLL. This is equivalent to the LSP ping for a VLL service. VCCV ping reuses an LSP ping message format and can be used to test a VLL configured over an MPLS, GRE, or IP SDP.
A 7705 SAR node using GNSS or IEEE 1588v2 PTP for time of day/phase recovery can perform VCCV ping tests with high-accuracy timestamping. See the 7705 SAR Basic System Configuration Guide, "Node Timing", for information about node timing sources.