Biblio

With the ever increasing growth of internet usage, ensuring high security for information has gained great importance, due to the several threats in the communication channels. Hence there is continuous research towards finding a suitable approach to ensure high security for the information. In recent decades, cryptography is being used extensively for providing security on the Internet although primarily used in the military and diplomatic communities. One such approach is the application of Chaos theory in cryptosystems. In this work, we have proposed the usage of combined multiple recursive generator (CMRG) for KEY generation based on a chaotic function to generate different multiple keys. It is seen that negligible difference in parameters of chaotic function generates completely different keys as well as cipher text. The main motive for developing the chaos based cryptosystem is to attain encryption that provides high security at comparatively higher speed but with lower complexity and cost over the conventional encryption algorithms.

Recently, the chaotic public-key cryptography attracts much attention of researchers, due to the great characters of chaotic maps. With the security superiorities and computation efficiencies of chaotic map over other cryptosystems, in this paper, a novel Identity-based signcryption scheme is proposed using extended chaotic maps. The difficulty of chaos-based discrete logarithm (CDL) problem lies the foundation of the security of proposed ECM-IBSC scheme.

This paper proposes a new hybrid technique for combined encryption text and image based on hyperchaos system. Since antiquity, man has continued looking for ways to send messages to his correspondents in order to communicate with them safely. It needed, through successive epochs, both physical and intellectual efforts in order to find an effective and appropriate communication technique. On another note, there is a behavior between the rigid regularity and randomness. This behavior is called chaos. In fact, it is a new field of investigation that is opened along with a new understanding of the frequently misunderstood long effects. The chaotic cryptography is thus born by inclusion of chaos in encryption algorithms. This article is in this particular context. Its objective is to create and implement an encryption algorithm based on a hyperchaotic system. This algorithm is composed of four methods: two for encrypting images and two for encrypting texts. The user chose the type of the input of the encryption (image or text) and as well as of the output. This new algorithm is considered a renovation in the science of cryptology, with the hybrid methods. This research opened a new features.

After a brief introduction on optical chaotic cryptography, we compare the standard short cavity, close-loop, two-laser and three-laser schemes for secure transmission, showing that both are suitable for secure data exchange, the three-laser scheme offering a slightly better level of privacy, due to its symmetrical topology.

In this paper, we present a new secure message transmission scheme using hyperchaotic discrete primary and auxiliary chaotic systems. The novelty lies on the use of auxiliary chaotic systems for the encryption purposes. We have used the modified Henon hyperchaotic discrete-time system. The use of the auxiliary system allows generating the same keystream in the transmitter and receiver side and the initial conditions in the auxiliary systems combined with other transmitter parameters suffice the role of the key. The use of auxiliary systems will mean that the information of keystream used in the encryption function will not be present on the transmitted signal available to the intruders, hence the reconstructing of the keystream will not be possible. The encrypted message is added on to the dynamics of the transmitter using inclusion technique and the dynamical left inversion technique is employed to retrieve the unknown message. The simulation results confirm the robustness of the method used and some comments are made about the key space from the cryptographic viewpoint.

Multivariate public key cryptosystem acts as a signature system rather than encryption system due to the minus mode used in system. A multivariate encryption system with determinate equations in central map and chaotic shell protection for central map and affine map is proposed in this paper. The outputs of two-dimension chaotic system are discretized on a finite field to disturb the central map and affine map in multivariate cryptosystem. The determined equations meet the shortage of indeterminate equations in minus mode and make the general attack methods are out of tenable condition. The analysis shows the proposed multivariate symmetric encryption system based on chaotic shell is able to resist general attacks.