MPLS 6PE
IPv6 Provider Edge (6PE) is an IPv4-to-IPv6 transition technology. This technology allows ISPs to provide access services for scattered IPv6 networks over existing IPv4 backbone networks. In this way, CEs on IPv6 islands can communicate with each other through IPv4 PEs.
- 6PE routers exchange IPv6 routing information with CEs using IPv6 routing protocols.
- 6PE routers exchange IPv6 routing information with each other using Multiprotocol Border Gateway Protocol (MP-BGP) and allocate MPLS labels to IPv6 prefixes.
- 6PE routers exchange IPv4 routing information with Ps using IPv4 routing protocols and establish LSPs between 6PE routers and Ps using MPLS.
Figure 1 shows the IPv6 packet forwarding process on an MPLS 6PE network. IPv6 packets must carry outer and inner labels when being forwarded on the IPv4 backbone network. The inner label (L2) maps the IPv6 prefix, while the outer label (L1) maps the LSP between 6PEs.
The MPLS 6PE technology allows ISPs to connect existing IPv4/MPLS networks to IPv6 networks by simply upgrading PEs. To Internet service providers (ISPs), the MPLS 6PE technology is an efficient solution for transition to IPv6.