Which statement describes SEND's security feature?

• A. A cryptographic security for sender address verification
• B. Increased speed of address resolution
• C. Requires no key management
• D. Eliminates all overhead

Answer: (A)

Secure Neighbor Discovery (SEND) adds cryptographic proof to IPv6 neighbor discovery messages, so receivers can trust that the sender really owns the advertised address. The core feature is cryptographic verification of the sender’s address, achieved through mechanisms like Cryptographically Generated Addresses (CGA) and digital signatures on neighbor solicitation and neighbor advertisement messages. This binding of an address to a public key lets other nodes verify the origin of NDP messages and prevents spoofing of both the address and the message. Because of this cryptographic layer, SEND focuses on ensuring that a host cannot impersonate another by simply sending fraudulent NDP traffic.

These choices don’t fit SEND’s purpose: increasing speed of address resolution would conflict with the extra cryptographic processing SEND requires, and saying no key management is needed ignores the cryptographic keys involved in CGA verification. Likewise, eliminating all overhead is inaccurate because the security features add processing and message size overhead.