The Need for VPLS
VPLS is a service that emulates an Ethernet LAN. The need for VPLS arose because MPLS VPN is a service that is IP centric. No other Layer 3 traffic can be carried across the MPLS backbone with this service. Any Transport over MPLS (AToM) allows you to carry all Layer 3 protocols as AToM carries the Layer 2 frames across the MPLS backbone; thus, AToM is not limited to carrying IP. The disadvantage of AToM is that it is point-to-point. Between each pair of PE routers is a pseudowire (two LSPs, one for each direction) that carries the Layer 2 frames. Metro Ethernet networks have seen a tremendous rise in popularity in the past few years because Ethernet is cheap, flexible, omnipresent, and easy to provision.
If a customer wants ...
Get MPLS Fundamentals now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
