Question

Which of the following statements is TRUE of encryption?

A. Every time an additional bit is added to a key length, it doubles the size of the possible keyspace.

B. A 64-bit encryption is currently the minimum length that is considered strong.

C. A 128-bit key encryption creates a keyspace exactly twice as long as 64-bit key encryption.

D. The algorithms involved are very complex and only privately known.

Answer 1

The statement that is true of encryption is:

A. Every time an additional bit is added to a key length, it doubles the size of the possible keyspace.

This statement is true because the number of possible keys that can be created increases exponentially as the key length increases. For example, a 64-bit key has 2^64 possible combinations, whereas a 128-bit key has 2^128 possible combinations. This means that it would take much longer to crack a 128-bit encryption compared to a 64-bit encryption. Therefore, it is common practice to use longer key lengths for stronger encryption.