A Lightweight Image Encryption Algorithm Based on Secure Key Generation

Data confidentiality and security are important issues due to the sensitivity of the data and its relationship with users’ privacy. Sensitive data includes images and texts that can be transmitted over the Internet, Internet of Things devices and edge-fog-cloud system. These devices require speed and accuracy responses, and they are vulnerable to hacking. To solve these problems, encryption algorithms provide necessary solution to meet these requirements. Advanced Encryption Standard represents the best development in data encryption; however, it is computational expensive. In this research, an improved advanced encryption standard algorithm is proposed with advanced security and lightweight computation utilized for encrypting of images and texts. The algorithm is improved using various steps including key generation which is performed in two steps. First, using an innovative, proven chaotic function distinguished by its sensitivity to any change in its variables. Second, using three-dimensional Lorenzo function. In our research, a unique key was used for all rounds, and round key then used like advanced encryption standard. Two new dynamic substitution boxes are used one for odd rounds and the other for even rounds in which the speed does not exceeding a millisecond. The mix column function was replaced by a circular permutation function at the bit level, which improved the speed and performance of the algorithm, Our extensive simulation results indicated enhanced speed, randomness, and high efficiency in encrypting Internet of Things data. The algorithm was evaluated using the National Institute of Standards and Technology tests.

Keywords: AES, Chaotic map, Circular permutation, Cryptography, Dynamic S-box, IoT, Lightweight algorithm.