Overview IPv6 BGP

IPv6 BGP (BGP4 +) is extended from BGP-4. BGP-4 can only manage IPv4 routing information. To support IPv6 protocol, IETF extends BGP-4 to form IPv6 BGP. The current IPv6 BGP standard is RFC 2858 (Multiprotocol Extensions for BGP-4).

IPv6 BGP needs to reflect IPv6 network layer protocol information into NLRI (Network Layer Reachability Information) and NEXT_HOP attributes. The two NLRI attributes introduced in IPv6 BGP are:

• MP_REACH_NLRI: Multiprotocol Reachable NLRI, used to release the reachable route and next-hop information
• MP_UNREACH_NLRI: Multiprotocol Unreachable NLRI, used to cancel the unreachable route

The NEXT_HOP attribute in IPv6 BGP is represented by an IPv6 address, which can be an IPv6 global unicast address or a link local address.

IPv6 BGP uses the multi-protocol extension attributes of BGP to realize the application in IPv6 network. The original message mechanism and routing mechanism of BGP the protocol do not change.