HCCIE: hexaflake fractals, chaotic maps, and cellular automata based image encryption technique for IoT

Abstract The exponential growth of digital information in the twenty first century necessitates secure handling, especially when dealing with sensitive visual data. Conventional encryption methods such as the Data Encryption Standard (DES), Advanced Encryption Standard (AES), and Rivest-Shamir-Adleman (RSA) are prevalent but inefficient for image-related applications due to their limitations for resource-constrained devices. Most conventional schemes exhibit high pixel correlation, increased computational complexity, limited robustness, and significant memory requirement. To address these issues, research has been conducted to develop a novel encryption technique “HCCIE", which utilizes hexaflake fractal (HF), chaotic maps, and Cellular Automata (CA). This paper proposes a novel fractal-based seed generation method for image shuffling. Subsequently, the paper focuses on a Modular Masked XOR (MMX) scheme to generate the pseudo-random mask to facilitate the image masking. Here, image shuffling enhances pixel randomization while MMX strengthens both confusion and diffusion properties for secure color image transfer. Experimental results confirm the strong security characteristics and robustness of the proposed scheme against various types of noise and data loss attacks. The scheme demonstrates improved performance, with a 19.91% enhancement in Mean Squared Error (MSE) and a 10.29% improvement in Peak Signal-to-Noise Ratio (PSNR), thereby making it well-suited for real-time applications. It also exhibits computational efficiency, achieving an average execution time of 1.4 s on an IoT device (Raspberry Pi 3 Model B v1.2). Furthermore, the proposed scheme successfully passed all evaluations in the National Institute of Standards and Technology (NIST) statistical test suite, confirming its cryptographic reliability.