Cellular automata based key distribution for lightweight hybrid image encryption with elliptic curve cryptography.

The paper presents a lightweight hybrid image encryption scheme for IoT applications. The method performs secure key exchange using ECC, derives random keys using the CA Rule Vector [90, 90, 51, 51, 92, 195, 195, 195], and encrypts the image using AES-128. The secret shared via ECC serves as the seed for the CA rule vector [90, 90, 51, 51, 92, 195, 195, 195], facilitating the generation of a highly dispersed and secure session key. The system generates a highly diffused key through CA and then uses it in the AES encryption process. The framework has been tested on standard images from the SIPI database and has shown strong security results with NPCR of 99.6461, UACI of 49.9927, and entropy of 7.9991 for the Baboon Image. The method has passed all NIST randomness tests and shows a superior execution time, making it highly suitable for lightweight encryption in resource-constrained IoT environments.