A Stream Cipher Algorithm based on Nonlinear Combination Generator with Enhanced Security for Image Encryption

Abstract

This paper describes a novel approach for image encryption using stream cipher algorithm based on non linear combination generator. This work aims to enhance the security of encrypted image. The work is based on the use of several linear feedback shifts registers whose feedback polynomials are primitive and of degrees are all pair wise cop rimes combined by resilient function whose resiliency order, algebraic degree and nonlinearity attain Siegenthaler's, Sarkar and al.'s bounds. This proposed approach is simple and highly efficient. The proposed algorithm was evaluated through a set of tests. In order to have a global idea of the whole performance of system, our tests included visual tests, histogram analysis, key space analysis, Berlkamp-Massey attack, correlation attack and algebraic attack. The results of the experimental tests demonstrate that the proposed system is highly key sensitive, highly resistant to noises and shows a good resistance against brute-force, statistical attacks, Berlekamp-Massey attack, correlation attack and algebraic attack. The system is robust which makes it a potential candidate for image encryption.

Κρυπτογραφία Με Χάος

“…The comparison of the proposed algorithms with the existing algorithms (where data is available) shows that the proposed encryption algorithms have very good values of the evaluation indicators even a little better compared to other ciphers for images (Abeer MY, Manaf MA, 2013) , (Ahmad J., Ahmed F., 2012), (Belmeguenai A., Redjimi M., Derouiche N., 2012) and (Gupta K., Silakari S., 2011).…”

“…Η σύγκριση των προτεινόμενων αλγορίθμων με του υφιστάμενους αλγορίθμους (όπου είναι διαθέσιμα δεδομένα) μας δείχνει ότι: 1) οι προτεινόμενοι αλγόριθμοι κρυπτογράφησης δεν παρουσιάζουν σημαντικές διαφορές ως προς τις επιδόσεις τους και 2) οι δείκτες αξιολόγησης έχουν πολύ καλές τιμές περίπου 5% καλύτερες από τις τιμές άλλων αλγορίθμων κρυπτογράφησης εικόνων (Abeer M.Y., Manaf M.A., 2013), (Ahmad J., Ahmed F., 2012), (Belmeguenai A., Redjimi M., Derouiche N., 2012) και (Gupta K., Silakari S., 2011 1) Κατασκευή διακριτοποίησης του μετασχηματισμού του Πλάστη (Baker Map) ώστε να μπορεί να εφαρμοστεί σε οποιοδήποτε πλέγμα διάστασης Ν×Μ (Ενότητα 5.1).…”