Article details

Title: Design of a Fast and Robust Chaos-Based Crypto-System for Image Encryption
Author(s): Hassan Noura   Safwan El Assad   C?lin Vl?deanu   

Abstract: In this paper, we propose a fast and robust scheme for image encryption including a new chaotic generator. The proposed crypto-system uses a variable block cipher length (8, 128, and 512), with different modes: cipher block chaining (CBC), output feedback (OFB), cipher feedback (CFB), and counter (CTR). The fastness and robustness properties of our crypto-system are determined by the chaotic generator using a 32-bit finite precision with integer representation to facilitate hardware implementation, and by a keystream permutation using a 2D cat map with chaotic control parameters. The chaotic generator is constructed with two non linear (the skew tent map) IIR filters. To quantify the security level of the proposed cryptosystem, we analyze the global dynamical properties of the chaotic generator using the NIST (National Institute of Standards and Technology) test, and we show that the algorithm can resist the statistical and differential attacks; it also passed the key sensitivity test. Moreover, the algorithm has a large key space. The experimental results indicate that the scheme is secure, efficient, and faster than conventional advanced encryption standard (AES).

Keywords: chaos-based crypto-system, chaotic generator, chaotic permutation, security analysis.

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