After the introduction and early adoption of Layer 3 virtual private networks (VPNs) based on RFC 4364 (also known as RFC 2547bis), many customers asked their service providers to offer VPNs that would preserve data at Layer 2. One of the Layer 2 VPN options that has emerged is known as a Layer 2 circuit. It is based on a series of Internet Engineering Task Force (IETF) drafts and RFCs authored by Luca Martini. These so-called “Martini-drafts” include Internet draft draft-martini-l2circuit-encap-mpls-11.txt, Encapsulation Methods for Transport of Layer 2 Frames Over MPLS Networks (expires August 2006) and Internet draft draft-martini-l2circuit-trans-mpls-19.txt, Transport of Layer 2 Frames Over MPLS (expires September 2006), and establish the basis for Juniper Networks implementation of Layer 2 circuits. This guide shows how to implement Layer 2 circuits in a variety of ways.
This feature guide covers these topics: