Ipv6 Mpls L3Vpn Routing Information Advertisement; Ipv6 Mpls L3Vpn Network Schemes And Functions - HP HSR6800 Configuration Manual

1. The PC at Site 1 sends an IPv6 packet destined for 2001:2::1, the PC at Site 2. CE 1 transmits
the packet to PE 1.
2. Based on the inbound interface and destination address of the packet, PE 1 searches the
routing table of the VPN instance. Finding a matching entry, PE 1 labels the packet with both
inner and outer labels and forwards the packet out.
3. The MPLS backbone transmits the packet to PE 2 by outer label. The outer label is removed
from the packet at the penultimate hop.
4. According to the inner label and destination address of the packet, PE 2 searches the routing
table of the VPN instance to determine the outbound interface and then forwards the packet out
of the interface to CE 2.
5. CE 2 forwards the packet to the destination by IPv6 forwarding.

IPv6 MPLS L3VPN routing information advertisement

The IPv6 VPN routing information for a local CE is advertised to a remote peer PE in the following
steps:
1. From the local CE to the ingress PE.
2. From the ingress PE to the egress PE.
3. From the egress PE to the remote peer CE.
A route becomes available from the local CE to the remote CE.
Routing information exchange from the local CE to the ingress PE
After establishing an adjacency with the directly connected PE, a CE advertises its IPv6 VPN routes
to the PE.
The routes between a CE and a PE can be IPv6 static routes, RIPng routes, OSPFv3 routes, IPv6
IS-IS routes, or EBGP routes. No matter which routing protocol is used, the CE always advertises
standard IPv6 routes to the PE.
Routing information exchange from the ingress PE to the egress PE
After learning the IPv6 VPN routes from the CE, the ingress PE adds RDs and route targets for these
standard IPv6 routes to create VPN-IPv6 routes, saves them to the routing table of the VPN instance
created for the CE, and then triggers MPLS to assign VPN labels for them.
Then, the ingress PE advertises the VPN-IPv6 routes to the egress PE through MP-BGP.
Finally, the egress PE compares the export target attributes of the VPN-IPv6 routes with the import
target attributes that it maintains for the VPN instance and, if they are the same, adds the routes to
the routing table of the VPN instance.
The PEs use an IGP to ensure the connectivity between them.
Routing information exchange from the egress PE to the remote CE
The exchange of routing information between the egress PE and the remote CE is the same as that
between the local CE and the ingress PE.

IPv6 MPLS L3VPN network schemes and functions

IPv6 MPLS L3VPN supports the following network schemes and functions:
•
Basic VPN
•
Inter-AS VPN option A
•
Inter-AS VPN option C
•
Carrier's carrier
•
Multi-VPN-instance CE
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