VPWS

VPWS, or Virtual Private Wire Service, is a type of Layer 2 VPN that provides a private, point-to-point connection between two customer edge devices across a provider’s MPLS network. It emulates a dedicated wire between two sites, allowing the customer to run their own Layer 2 protocols and addressing over the WAN while the service provider handles the transport and security.

In operation, a pair of provider edge (PE) routers terminate the pseudowire that forms the VMPS between the customer sites. The customer edge (CE) devices connect to the PE routers, and the provider encapsulates the CE traffic as pseudowire payloads carried over an MPLS label-switched path. The encapsulation is commonly Ethernet over MPLS (EoMPLS), but VPWS can also support other Layer 2 technologies such as TDM in legacy deployments. The remote PE decapsulates and delivers frames to the distant CE, preserving the appearance of a direct link.

Signaling for pseudowires is typically achieved via MPLS control plane protocols such as LDP or RSVP-TE, and can be configured statically in some networks. VPWS is distinct from VPLS, which provides multipoint-to-multipoint connectivity; VPWS is strictly point-to-point, suitable for site-to-site connections that function like a private leased line.

Common use cases include connecting two branch offices, extending an Ethernet LAN across locations, or linking data centers with a predictable, isolated L2 transport. Benefits include straightforward deployment and support for various L2 services; tradeoffs involve scalability considerations and reliance on the provider for network-wide isolation and performance.