Mpls L3Vpn Implementation - H3C S9500 Series Operation Manual

Operation Manual – MPLS L3VPN
H3C S9500 Series Routing Switches
When matching the VPN Target attribute carried by the route to filter the routing
information received by the PE router, if the export VPN target set of the received route
contains identical items with the import VPN target set of the local end, the route is
imported into the VPN routing table and then advertised to the connected CE .
Otherwise, the route will be rejected.
Figure 1-3 Route filtering through matching VPN Target attribute
Note:
The routes for other VPNs will not appear in the VPN's routing table by using VPN
Target attribute to filter routing information received at PE router, so the CE-transmitted
data will only be forwarded within the VPN.
V. Routing policy
If the advertisement of routing information needs to be controlled in a more accurate
manner than using egress extended community attributes only, you can use an
outgoing routing policy.
In the outgoing routing policy you can set specific extended community attributes for
specific routes to be advertised.
After creating a VPN instance, you can choose whether to configure an outgoing
routing policy for it.

1.1.2 MPLS L3VPN Implementation

MPLS L3VPN works on this principle: It uses BGP to propagate VPN private routing
information on carrier backbone network, and uses MPLS to forward VPN service
traffic.
The following are introductions to MPLS L3VPN implementation from two aspects:
advertising VPN routing information and forwarding VPN packets.
I. Advertising VPN routing information
Routing information exchange has the following four types:
Chapter 1 MPLS L3VPN Configuration
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