Which security property does IPsec provide to prevent replay attacks?

Which security property does IPsec provide to prevent replay attacks?

• A. Biometric authentication
• B. Data minimization
• C. Denial of service prevention
• D. Replay protection

Answer: (D)

The key idea is IPsec’s anti-replay mechanism. IPsec assigns a increasing sequence number to each packet, and the receiver uses a sliding window to track those numbers. If a packet arrives with a duplicate or a stale sequence number, it is dropped, which stops an attacker from re-sending a captured packet to fool the recipient. This specific protection is what prevents replay attacks, ensuring that old copies of data aren’t accepted as new. Biometric authentication, data minimization, and denial-of-service prevention address other security concerns and don’t directly tackle replayed network packets.

The key idea is IPsec’s anti-replay mechanism. IPsec assigns a increasing sequence number to each packet, and the receiver uses a sliding window to track those numbers. If a packet arrives with a duplicate or a stale sequence number, it is dropped, which stops an attacker from re-sending a captured packet to fool the recipient. This specific protection is what prevents replay attacks, ensuring that old copies of data aren’t accepted as new. Biometric authentication, data minimization, and denial-of-service prevention address other security concerns and don’t directly tackle replayed network packets.