Implementing and Operating Cisco Security Core Technologies (SCOR) — Question 281

An engineer is configuring IPsec VPN and needs an authentication protocol that is reliable and supports ACK and sequence. Which protocol accomplishes this goal?

Answer options

• A. AES-256
• B. IKEv1
• C. ESP
• D. AES-192

Correct answer: C

Explanation

The correct answer is C, ESP, as it provides encryption, integrity, and authentication while also supporting acknowledgment and sequencing. Options A and D, AES-256 and AES-192, are encryption algorithms that do not handle authentication protocols. Option B, IKEv1, is primarily for key exchange and does not fulfill the need for ACK and sequence support in the same way ESP does.