A New Lightweight Encryption Method Based on the DNA-RC4 Substitution for Resource-Constrained IoT Devices

Technology's impact on daily life necessitates increased data protection. Cryptographic systems improve security, ensuring confidentiality and legitimacy of Internet of Things systems. However, resource-constrained devices face challenges like memory, battery life, processing power, and small size. In light of this, lightweight cryptography (LWC) provides techniques specifically tailored to the constraints of resource-constrained Internet of Things devices. However, the presence of a fixed S-Box in some LWC algorithms, such as Advanced Encryption Standard, or the absence of one in others, such as Speck and Tiny Encryption Algorithm, renders them more susceptible to attacks. In this paper, we suggest a new lightweight encryption method (NeLEM) based on the DNA-RC4 substitution for resource-constrained IoT devices. NeLEM is an innovative one-round lightweight encryption method that uses a 16 × 16 substitution S-box. NeLEM combines the high complexity feature found in DNA sequences with the RC4's light and fast algorithm. NeLEM uniquely balances robust security with computational simplicity, ensuring that the S-box is cryptographically strong and lightweight. By integrating the inherent unpredictability and nonlinearity of DNA with the streamlined simplicity of RC4, NeLEM generates highly efficient S-boxes capable of resisting cryptanalytic attacks while keeping resource consumption minimal. We conduct several security tests on the suggested scheme to evaluate the strength of the encryption method. These tests include histogram analysis, entropy, correlation coefficient, encryption quality (PSNR, MSE, MD, ID), and how well it stands up to different noise attacks. Using randomness tests like the NIST Statistical Test Suite, the results also showed how well the proposed NeLEM creates reliable random sequences. We implement the suggested NeLEM using the ESP32 microcontroller. In terms of efficiency and security level, NeLEM is compared with a popular lightweight encryption algorithm, Speck. According to the experiment's findings, the suggested NeLEM outperforms Speck by 6.7 times, High productivity was achieved that exceeds both algorithms.