A hybrid-key based image encryption and authentication scheme with the use of ergodic matrix

Abstract

The chaos-based cryptosystems have certain advantages over the traditional encryption algorithms due to their higher speed and lower costs. However, the existing chaos based cryptosystems are almost all based on symmetric cryptography. Symmetric cryptography is much faster than asymmetric ciphers, but the requirements for key exchange make them hard to use. Furthermore, most of the chaos-based cryptosystems cannot authenticate whether the message is exactly sent by the one. To remedy this imperfection, a hybrid-key based image encryption and authentication scheme is proposed in this paper. Particularly, ergodic matrices are utilized not only as public keys in the encryption/decryption process, but also as essential parameters in the confusion and diffusion stages. The results of several experiments, statistical analysis and sensitivity based tests confirm that compared to the existing chaos-based cryptosystems, the proposed scheme provides more secure way for image encryption and network transmission