Analysis on AES encryption standard and safety

AES has replaced DES to become a widely used encryption algorithm since 2000s. This paper may insight the basic theory of AES and safety analysis. In this paper, the whole process of AES encryption is described. The procedures of plaintext processing firstly, substituting bytes secondly, then shifting rows, mixing columns and adding round keys. AES-128 is taken as the study example in this paper to introduce the features and operating steps of AES. The construction and use of a simple S-box is also mentioned to help understand the procedure of substituting bytes. Safety analysis of AES is also taken into consideration to test AES’s resistance against different kinds of attacks. The results show that AES is free from brute force attack with time security analysis. AES with 128 or more bits of key length can resist square attacks according to reviews on research. A way of differential cryptanalysis attack with concrete operating steps is introduced as a potential attack method against AES encryption standard. The paper also casts view on an improved AES algorithm to increase efficiency and security proposed by other research.