ABSTRACT
The Advanced Encryption Standard (AES) is a renowned symmetric key algorithm that utilizes a same secret key to encrypt and decrypt a message. It overcomes the limitation of the smaller key size of the Data Encryption Standard (DES) by utilizing
Keywords 91 6.1 Overview 91 6.2 History 92 6.3 Design Consideration 93 6.4 Primitive Operations of AES 94 6.5 Structure of AES 100 6.6 Overview of Key Expansion 100 6.7 Key Expansion Example 103 6.8 Encryption 103 6.9 An Encryption Example 104 6.10 Decryption 104 6.11 Limitations 106 6.12 Pros and Cons of AES 106 6.13 Implementation 107 6.14 Conclusion 126
a bigger and variable-length key that may take 149 trillion years to crack (assuming a machine could try 255 keys per secondNational Institute of Standards and Technology [NIST]). Moreover, it also resolves the slow processing speed of Triple DES (3DES) and utilizes lower resources than that. Therefore, it is preferred as the encryption and decryption standard by the U.S. government. This standard is described in Federal Information Processing Standard (FIPS). AES is now being used worldwide for encrypting digital information, including financial, telecommunications, and government data.
