BGP is used with BGP extensions to distribute VPRN routing information across the service provider's network. BGP was initially designed to distribute IPv4 routing information. Therefore, multi-protocol extensions and the use of a VPN-IPv4 address were created to extend BGP's ability to carry overlapping routing information. A VPN-IPv4 address is a 12-byte value consisting of the 8-byte route distinguisher (RD) and the 4-byte IPv4 IP address prefix. The RD must be unique within the scope of the VPRN. This allows the IP address prefixes within different VRFs to overlap.
The 7210 SAS-K 2F6C4T and 7210 SAS-K 2F6C4T provide 6PE support in the base routing instance with BGP 3017 labeled routes to interconnect IPv6 networks over an IP/MPLS infrastructure.