Implementing Cisco Network Security (IINS, legacy) — Question 85

In a brute-force attack, what percentage of the keyspace must an attacker generally search through until he or she finds the key that decrypts the data?

Answer options

• A. Roughly 50 percent
• B. Roughly 66 percent
• C. Roughly 75 percent
• D. Roughly 10 percent

Correct answer: A

Explanation

The correct answer is A, as in a brute-force attack, statistically, an attacker would need to check about 50 percent of the keyspace to have a good chance of finding the correct key. Options B, C, and D represent percentages that are either too high or too low for an effective brute-force strategy.