# VPLS Protocol Overview

JunosE Software enables you to configure one or more instances of VPLS, referred to as VPLS instances, on the router. VPLS employs an Ethernet-based layer 2 VPN to connect multiple individual LANs across a service provider’s MPLS core network. The geographically dispersed multiple LANs function as a single virtual LAN. VPLS provides a point-to-multipoint capability for traffic forwarding. In contrast, L2VPNs that enable a virtual private wire service (VPWS) provide only a point-to-point traffic forwarding capability.

VPLS preserves the broadcast and multicast capabilities of the physical LANs. Consequently, any broadcast or multicast traffic from a given customer end station is sent to all sites that participate in the VPLS instance.

You can use either BGP or LDP to provide signaling for VPLS, as follows:

- BGP signaling—VPLS with BGP signaling, which is referred to as BGP-based VPLS, uses BGP as the protocol that signals reachability for the VPLS domain in which the VPLS instance participates. You must configure BGP on each provider edge (PE) router in your topology to provide signaling for each VPLS domain.
- LDP signaling—VPLS with LDP signaling, which is referred to as LDP-based VPLS, uses LDP as the protocol that signals reachability for the VPLS domain in which the VPLS instance participates. You must configure LDP on each PE router in your topology to provide signaling for each VPLS domain.

Figure 128 illustrates an example of a simple VPLS topology. The basic topology of a VPLS network is the same regardless of whether BGP signaling or LDP signaling is used.

Figure 128: VPLS Sample Topology

#### Related Topics

- BGP Signaling for VPLS Overview
- Configuring VPLS with BGP Signaling on a PE Router in Configuring VPLS
- LDP Signaling for VPLS Overview
- Configuring VPLS with LDP Signaling on a PE Router in Configuring VPLS
- Configuring BGP-MPLS Applications
- Configuring VPWS