Chapter 14: Virtual Private LAN Services (VPLS)
Multiprotocol Label Switching (MPLS) is generally accepted as the common convergence technology and facilitates the deployment and management of Virtual Private Networks (VPNs). MPLS-based VPN can be classified as either a layer 2 [1, 2] or a layer 3 point-to-point service or multipoint service:
VPLS is a multipoint service, but unlike IP VPNs, it can transport non-IP traffic and leverages advantages of Ethernet. VPLS is also used within a service provider's (SP) network to aggregate services for delivery to residential and enterprise customers.
Regardless of how the VPN service is used, most enterprise customers use routers at the LAN/WAN boundary. However, VPLS is a layer 2 VPN service and allows the use of layer 2 switches as the customer edge (CE) device.
VPLS is introduced by RFC 2764 , as a VPN service, which emulates a LAN segment using IP-based facilities (Fig. 14.1) for a given users. In other words, VPLS creates a layer 2 broadcast domain that is fully capable of learning and forwarding on Ethernet Media Access Control (MAC) addresses. Multiple CEs such as bridges, router, layer ...