# VPWS and BGP/MPLS VPNs Overview

BGP multiprotocol extensions (MP-BGP) enable BGP to support IPv4 services such as BGP/MPLS VPNs, which are sometimes known as RFC 2547bis VPNs. A VPWS L2VPN is actually a BGP-MPLS application that has much in common with BGP/MPLS VPNs.

The procedures for configuring BGP signaling for BGP/MPLS VPNs and for VPWS L2VPNs are similar except that for VPWS L2VPNs you must configure both of the following address families:

- L2VPN—The L2VPN address family enables you to configure the PE router for VPWS (or VPLS) L2VPNs to exchange layer 2 network layer reachability information (NLRI) for all VPWS (or VPLS) instances. Optionally, you can use the signaling keyword with the address-family command for the L2VPN address family to specify BGP signaling of VPWS reachability information. Currently, you can omit the signaling

  keyword with no adverse effects.

- VPWS—The VPWS address family enables you to configure the PE router to exchange layer 2 NLRI for a specified VPWS instance.

BGP can exchange information in an L2VPN topology within these address families.

#### Related Documentation

- Configuring BGP Routing
- Configuring BGP-MPLS Applications