How many encryption key bits are needed to double the number of possible key values that are available with a 40-bit encryption key?
- 41 bits
- 80 bits
- 120 bits
- 160 bits
Explanation & Hint: To double the number of possible key values available with a 40-bit encryption key, you would only need to add one more bit:
- 41 bits
Each additional bit doubles the number of possible keys because each bit has two possible values (0 or 1). Therefore, going from a 40-bit key to a 41-bit key doubles the number of possible keys from 240 to 241.