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VPLS C
ONFIGURATION
The service processor card mentioned in this chapter refers to the 3C17548 VPLS 
Application Module.
VPLS Overview
Introduction to VPLS
Today, IP networks have spread throughout the world. And the operators are 
focusing on using their existing IP networks to provide enterprises with low-cost 
private networks. Now, an easily implemented technique called MPLS VPN 
(multiprotocol label switching VPN) emerges as the times require, which enables 
the operators to provide arbitrary-rate MPLS-based virtual private network (VPN) 
services over IP networks.
MPLS VPN services fall into two types: L3 MPLS VPN and L2 MPLS VPN. The latter 
includes VPLS (virtual private LAN service) and VLL (virtual leased line). VLL only 
applies to point-to-point networking, while VPLS can apply to 
multipoint-to-multipoint VPN networking. VPLS provides the operators using 
point-to-point L2VPN with a better solution. In addition, unlike L3VPN, VPLS does 
not participate in user’s internal routing. Now, operators need only manage and 
operate a single network to provide multiple kinds of services such as best-effort, 
L3VPN, L2VPN, traffic-engineering, and distinguished services. This greatly reduces 
their costs on network construction, operation and maintenance.
With VPLS, users in different areas can be connected with each other through 
MAN/WAN just like they are in one LAN. Switch 8800 Family series provide a VPLS 
solution. This solution uses MPLS-based virtual links as the links of Ethernet 
bridges and provides transparent transmission LAN services (TLS) over MPLS 
networks.
The following table lists the acronyms referred in this document:
Table 568   Acronyms
Acronym 
Full name 
AC 
Attachment Circuit 
CE 
Customer Edge 
FEC 
Forwarding Equivalence Class 
FR 
Frame Relay 
NPE 
Network Facing PE 
PE 
Provider Edge Router 
PW 
Pseudowire 
PHP 
Penultimate Hop Popping