Standard encryption algorithm at first (since 1973) is the DES (Data Encryption Standard). However, the security of DES has been questioned by the U.S. around 1993. This is because the development of computer technology can not be matched by the design of the DES algorithm itself [9]. Therefore, the National Institute of Standards and Technology (NITS) held a contest to find a new standard encryption algorithm in 1997. Standard new algorithm is named AES (Advanced Encryption Standard)