Lightweight Modifications in the Advanced Encryption Standard (AES) for IoT Applications: A Comparative Survey

The Internet of Things is a network of billions of interconnected devices that communicate over the internet. These massive devices exchange massive amounts of data every second, and that data may be sensitive and must be protected from attackers. A cryptographic solution could be used to address these issues. Conventional cryptography is unsuitable for IoT devices with limited resources; lightweight cryptography is an alternative solution. Many researchers have presented new designs and modified the existing algorithms to become lightweight versions. This paper presents a recent comparison among numerous modifications of the very popular block cipher AES-128 algorithm that have been published between 2016 and 2021 in the light-weight symmetric block cipher cryptographic field based on security, throughput, and encryption time with various message lengths. The results of the comparison indicate that the modifications, which included modifying the ShiftRow operation, modifying the MixColumn operation and combining it with the AddRoundKey operation to perform in a single cycle, and reducing the number of rounds to 6, were faster in implementation and had greater security than other studies cited.