Virtual Private Lan Service (Architecture)

VPLS is widely deployed to provide private Ethernet bridging services over geographically separated locations. VPLS is a multipoint Layer 2 VPN with IP/MPLS as its backbone. VPLS takes full advantage of the resiliency, flexibility, scalability, and reliability of IP/MPLS VPN service architecture. VPLS services are deployed by carriers, service providers, and large enterprises that require highly available Ethernet services with high performance and guaranteed Quality of Service (QoS). VPLS is also referred to as Transparent LAN Service (TLS). VPLS enhances the service offering for service providers who have already deployed an MPLS backbone complementing the Layer 3 Virtual Private Routed Network (VPRN) services. VPLS was enhanced with the features destined to address the Carrier ETH requirements in different market segments. VPLS is used as an end-to-end Ethernet service or as an aggregation to IP VPN PE for the business services market, as DSLAM/PON aggregation and video distribution media for Triple Play, or as Mobile Backhaul aggregation for wireless solutions. VPLS service also inherits all the benefits brought by the MPLS infrastructure, such as traffic engineering on the service transport tunnels, rich tunnel resiliency features, and converged backbone for deploying multiple services. Service policies such as QoS, security, and accounting are deployed on the individual SAPs of service instances and can be different for the ingress direction and the egress direction. These benefits are strong market drivers for VPLS, increasing its popularity among service providers and enterprises.