H3C Technologies H3C S10500 Series Switches - Manual (Page 171)

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VPLS configuration
NOTE:
To support VPLS, the H3C S10500 Switch Series must use an SE, EA, or EB card, and use the ports on the
card to connect to the user network and carrier network.
VPLS overview
Virtual Private LAN Service (VPLS), also called “Transparent LAN Service (TLS)” or “virtual private
switched network service”, can deliver a point-to-multipoint Layer 2 VPN service over public networks.
With VPLS, geographically-dispersed sites can interconnect and communicate over MAN or WAN as if
they were on the same LAN.
VPLS provides Layer 2 VPN services. However, it supports multipoint services, rather than the
point-to-point services the traditional VPN supports. With VPLS, service providers can create a series of
virtual switches for customers on the PEs, allowing customers to build their LANs across the Metropolitan
Area Network (MAN) or Wide Area Network (WAN).
Operation of VPLS
Basic VPLS concepts
• CE
Customer edge device directly connected to the service provider network.
• PE
Provider edge device connecting one or more CEs to the service provider network. A PE maps and
forwards packets between private networks and public network tunnels. A PE can be a UPE or NPE.
• UPE
User facing provider edge device that functions as the user access convergence device.
• NPE
Network provider edge device that functions as the network core PE. An NPE resides at the edge of a
VPLS network core domain and provides transparent VPLS transport services between core networks.
• VSI
Virtual switch instance that maps actual access links to virtual links.
• PW
Pseudo wire that is the bidirectional virtual connection between VSIs. A PW consists of two unidirectional
MPLS virtual circuits (VCs).
• AC
Attachment circuit connecting the CE to the PE. It can use physical interfaces or virtual interfaces. Usually,
all user packets on an AC, including Layer 2 and Layer 3 protocol messages, must be forwarded to the
peer site without being changed.