I. Introduction
As computers and networks have reached each corner of human life geographically and practically, security and privacy become major concerns. Traditional data encryption/decryption is a computationally intensive task. Since it takes up lots of resources on the computing and communication endpoints, both computation and communication activities can be slowed down. Therefore, faster and more secure cryptographic algorithms are on demand. Advanced Encryption Standard (AES) is one of such widely used symmetric key cryptographic algorithms. It has reduced the computational operations dramatically in data encryption and decryption whereas its implementation structure exhibits a high degree of data parallelism for further performance elaboration. Theo-retically, AES is an extra burden for security and its execution time should be reduced. Further accelerator is expected to exploit its rich parallelism.