You are reviewing the Layer 2 VPN service offering of a service provider. A top priority is meeting SLAs for its customers. Which OAM standard should you recommend to monitor customer VPLS connectivit

OAM for MPLS Networks (RFC 4379) defines LSP Ping and LSP Traceroute, which verify MPLS data plane forwarding by directly testing the LSPs that transport VPLS pseudowires between PE routers. These mechanisms allow service providers to detect LSP failures and measure path performance, which is essential for meeting VPLS SLAs. Because VPLS connectivity depends entirely on correct MPLS forwarding, MPLS OAM is the foundational standard for monitoring it.

Connectivity Fault Management (IEEE 802.1ag) is an Ethernet-layer OAM standard for monitoring Ethernet segments, not the MPLS transport paths that carry VPLS pseudowires between PEs.

Ethernet in the First Mile (IEEE 802.3ah) is scoped to point-to-point Ethernet access links only and provides no mechanism for monitoring multi-point VPLS connectivity across an MPLS core.

E-LMI (MEF 16) is a protocol for signaling service attributes between CE and PE devices and does not perform active connectivity monitoring or provide path-level fault detection.