Ccna routing and Switching Complete Study Guide

Layer 2 MPLS VPN    Layer 2 VPNs are a type of virtual private network (VPN) that use 

MPLS labels to transport data. The communication occurs between routers known as 

provider edge routers (PEs) because they sit on the edge of the provider’s network, next to 

the customer’s network.

Internet providers who have an existing layer 2 network can opt to use these VPNs instead 

of the other common layer 3 MPLS VPNs.

There are two typical technologies of layer 2 MPLS VPNs:

Virtual private wire service (VPWS)    VPWS is the simplest form for enabling Ethernet 

services over MPLS. It is also known as ETHoMPLS (Ethernet over MPLS), or VLL 

(Virtual Leased Line). VPWS has the characteristics of a fixed relationship between an 

attachment-virtual circuit and an emulated virtual circuit. VPWS-based services are 

point-to-point, such as, for example, Frame-Relay/ATM/Ethernet services over IP/MPLS.