Increasing Key Size in Cryptography: Why It Matters

Why is increasing the size of a key important in cryptography?

a. It exponentially decreases the number of guesses a hacker needs to crack the key.

b. It linearly decreases the number of guesses a hacker needs to crack the key.

c. It linearly increases the number of guesses a hacker needs to crack the key.

d. It exponentially increases the number of guesses a hacker needs to crack the key.

Answer:

The correct answer is that increasing the size of a key exponentially increases the number of guesses a hacker needs to crack the key.

Explanation:

Among the options, the true statement is: d. increasing the size of a key exponentially increases the number of guesses a hacker needs to crack the key.. That's because the size of a key in cryptographic algorithms directly impacts the number of attempts needed to guess it, known as the key space. In simple terms, a key is like a password, and the larger it is, the more possibilities there are to guess. Let's say a key is 2 bits long, the key space is 4 (2^2). Now, if the key size increases exponentially to 4 bits, the key space now is 16 (2^4). With each bit that we add to the size of the key, the key space i.e., the number of possible keys, grows exponentially (doubles).