HPE FlexNetwork 5510 HI Series, Руководство по настройке Mpls

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Configuring VPLS
Overview
Virtual Private LAN Service (VPLS) delivers a point-to-multipoint L2VPN service over an MPLS or IP
backbone. The provider backbone emulates a switch to connect all geographically dispersed sites of
each customer network. The backbone is transparent to the customer sites, which can communicate
with each other as if they were on the same LAN.
Basic VPLS architecture
Figure 94 Basic VPLS architecture
As show in Figure 94 , the VPLS architecture mainly includes the following components:
•
CE —A customer edge device is directly connected to the service provider network.
•
PE —A provider edge device connects one or more CEs to the service provider network. A PE
implements VPN access by mapping and forwarding packets between private networks and
public network tunnels. A PE can be a UPE or NPE in a hierarchical VPLS.
•
AC —An attachment circuit, physical or virtual, connects a CE and a PE, such as an Ethernet
link or a VLAN.
•
PW —A pseudowire is a bidirectional virtual connection between two PEs. An MPLS PW
consists of two unidirectional MPLS LSPs in opposite directions.
•
Tunnel —A tunnel can be an LSP tunnel or an MPLS TE tunnel. It carries one or more PWs over
an IP/MPLS backbone. If a PW is carried on an LSP or MPLS TE tunnel, each packet on the
PW contains two labels. The inner label is the PW label, which identifies the PW and makes
sure the packet is forwarded to the correct VSI. The outer label is the public LSP or MPLS TE
tunnel label, which makes sure the packet is correctly forwarded to the remote PE.
•
VPLS instance —A customer network might include multiple geographically dispersed sites
(such as site 1 and site 3 in Figure 94 .) The service provider uses VPLS to connect all the sites
VPN 1
CE 1
PE 3
PE 1 PE 2
CE 2
MPLS or IP backbone
PW
PE 4
PW
PW PW
Site 1
VPN 2
Site 2
CE 3
VPN 1
Site 3
VPN 2
CE 4
Site 4
AC
AC AC
AC
PW PW
Tunnel
Tunnel
T
unnel
T
unnel
Tunnel
Tunnel