IPsec for IPv6 routing protocols
You can use IPsec to protect routing information and defend against attacks for these IPv6 routing protocols: OSPFv3, IPv6 BGP, and RIPng. IPsec enables these IPv6 routing protocols to encapsulate outbound protocol packets and de-encapsulate inbound protocol packets with the AH or ESP protocol. If an inbound protocol packet is not IPsec protected, or fails to be de-encapsulated, for example, due to decryption or authentication failure, the routing protocol discards that packet.
You must manually configure SA parameters in an IPsec policy for IPv6 routing protocols. The IKE key exchange mechanism is applicable only to one-to-one communications. IPsec cannot implement automatic key exchange for one-to-many communications on a broadcast network, where routers must use the same SA parameters (SPI and key) to process packets for a routing protocol.