Enhanced AES-256 cipher round algorithm for IoT applications

Abstract

Objectives: Networks have become a significant mode of communication in recent years. As a result, internet security has become a critical requirement for secure information exchange. Cryptography is used to securely send passwords over large networks. Cryptographic algorithms are sequences of processes used to encipher and decipher messages in a cryptographic system. One of those is the Advanced Encryption Standard (AES), which is a standard for data encryption in hardware and software to hide sensitive and vital information. The main objective is to design an AES system with modifications by the addition of primitive operations which can withstand several attacks and is more efficient.Method: AES works with three different key lengths: 128-bit keys, 192- bit keys, and 256-bit keys. The early rounds of AES have a poor diffusion rate. Better diffusion properties can be brought about by putting in additional operations in the cipher round and key generation algorithm of the conventional AES.Findings: The diffusion characteristics of the conventional AES and the proposed methodology are compared using the avalanche effect. The proposed AES algorithm shows an increased avalanche effect, which proves it to be more secure than the conventional AES. The proposed algorithm is executed on Vivado 2016.2 ISE Design Suite and the results are targeted on Zybo–Zynq Z-7010 AP SoC development board.Novelty: In addition, this paper also proposes an improved AES algorithm that was accomplished by altering the sub-bytes operation. This change was made to make it more reliant on round keys. This algorithm was also extended to a higher key length of 256 bits which makes the algorithm less vulnerable to attacks.