Juniper BGP, Configuration Manual

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Chapter 9
VPLS Overview
This chapter describes the virtual private LAN service (VPLS), and contains the
following sections:
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VPLS Overview on page 575
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VPLS Components on page 576
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VPLS and Transparent Bridging on page 577
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BGP Signaling for VPLS on page 579
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LDP Signaling for VPLS on page 579
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BGP Multihoming for VPLS on page 580
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VPLS Supported Features on page 585
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VPLS Platform Considerations on page 585
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VPLS References on page 586
VPLS 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:
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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.
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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.
VPLS Overview
■ 575