Options

• Native (+socket)

• Both in NDP and in the daemon
• Or with extensions to socket interface
• Sender side: appends required options.
• Receiver side: provides verification information via CMSG

• XFRM

• How to tell application the status of verification?
• NDP message are not always “dropped” even if the messages are not verified; they are treated as “unverified” messages.

• Netfilter

• Similar to XFRM

• Hmm...