Patent ID: 8774402
Filing Date: 2014-07-08
Classification: H04L

Abstract:
1. An encryption/decryption apparatus using an advanced encryption standard (AES) Rijndael algorithm, comprising: a computer system comprising a processor and a memory; a round key memory that stores (i) a round key for a first round and (ii) a plurality of respective first partial round keys of round keys for second to last rounds, wherein of the round keys for the second to last rounds, only the respective first partial round keys are stored in the round key memory; a round key operator, operating on the computer system, that receives from the round key memory the round key for the first round and the respective first partial round keys, and performs arithmetic operations on the round key for the first round and the respective first partial round keys for second to last rounds to generate AES round keys for the second to last rounds, wherein the round key memory stores the plurality of respective first partial round keys prior to the round key operator performing arithmetic operations on the round key for the first round; and a round executor operating on the computer system to perform an encryption or decryption operation using the round key for the first round and the AES round keys.