Enhancing the Performance of Symmetric-Key Cryptography via Instruction Set Extensions

In this paper, instruction set extensions for a reduced instruction set computer processor are presented to improve the software performance of the data encryption standard (DES), the triple DES, the international data encryption algorithm (IDEA), and the advanced encryption standard (AES) algorithms. The most computationally intensive operations of each algorithm are off-loaded to a set of newly defined instructions. The additional hardware required to support these instructions is integrated into the processor´s data path. For each of the targeted algorithms, comparisons are presented between traditional software implementations and new implementations that take advantage of the extended instruction set architecture. Results show that the utilization of the proposed instructions significantly reduces program code size, and improves encryption and decryption throughput. Moreover, the additional hardware resources required to support the instruction set extensions increase the total area of the processor by less than 65%. Finally, it will be shown that the throughputs for triple DES, IDEA, and AES are approximately the same when accelerated via instruction set extensions. This allows for seamless and transparent algorithm agility as one algorithm may be easily replaced by another algorithm with minimal performance degradation.