Input (grade 7): Examples The block cipher Rijndael/AES uses a key of up to 256 bits, resulting in a key space containing over 1.1579 × 1077 keys.
Output (grade 6): Examples The block cipher Rijndael/AES uses a key of up to 256 bits, resulting in a key space containing about 2256 which is over 1.1579 × 1077 keys.