Configuring 6PE
IPv6 provider edge (6PE) is a transition technology that uses MPLS to connect sparsely populated IPv6 networks through an existing IPv4 backbone network. It is an efficient solution for ISP IPv4/MPLS networks to provide IPv6 traffic switching capability.
Figure 67: Network diagram for 6PE
6PE mainly performs the following operations:
6PE assigns a label to IPv6 routing information received from a CE router, and sends the labeled IPv6 routing information to the peer 6PE device through an MP-BGP session. The peer 6PE device then forwards the IPv6 routing information to the attached customer site.
6PE provides tunnels over the IPv4 backbone so the IPv4 backbone can forward packets for IPv6 networks. The tunnels can be GRE tunnels, MPLS LSPs, or MPLS TE tunnels.
Upon receiving an IPv6 packet, 6PE adds an inner tag (corresponding to the IPv6 packet) and then an outer tag (corresponding to the public network tunnel) to the IPv6 packet. Devices in the IPv4 backbone network forwards the packet based on the outer tag. When the peer 6PE device receives the packet, it removes the outer and inner tags and forwards the original IPv6 packet to the attached customer site.
To implement exchange of IPv6 routing information, you can configure IPv6 static routing, an IPv6 IGP protocol, or IPv6 BGP between CE and 6PE devices.
For more information about MPLS, MPLS TE, CE, and P, see MPLS Configuration Guide. For more information about GRE, see Layer 3—IP Services Configuration Guide.