In this paper a novel symmetric protocol to cipher digital images is introduced. The protocol proposed consists of two iterative phases: The confusion phase and the diffusion phase. The first stage permutes the pixels in the image using a discrete chaotic map (specifically, the Cat map), whereas in the second stage, the pixel values (that is, the color of each pixel) are modified sequentially by means of a reversible memory cellular automata. The proposed protocol is shown to be secure against the more important cryptanalytic attacks.
['A. Martín del Rey', 'G. Rodríguez Sánchez', 'A. de la Villa Cuenca']
Encrypting digital images using cellular automata