CELLULAR AUTOMATA CRYPTOGRAPHIC MODEL BASED ON BI-DIRECTIONAL TOGGLE RULES
Gina M. B. Oliveira, A. R. COELHO, L.H.A. Monteiro · International Journal of Modern Physics C · 2004
Cellular automata (CA) are discrete dynamical systems that can be employed as cryptography algorithms. Irreversible CA with toggle rules — either to the right or to the left — were already proposed for encrypting. However, the similarity between ciphertexts when the plaintext is submitted to a small perturbation was identified as a flaw in this model. Here, such a model is altered by using bi-directional toggle CA rules instead of one-directional ones. Numerical experiments showed that the similarity flaw was eliminated by considering this modification, obtaining protection against differential cryptanalysis.