Cryptography based on Chaotic Synchronization: Round III

Nonlinear Analysis: Real World Applications, 2007

In this work we present a thorough investigation of the effect of noise (internal or external) on the synchronization of a driveresponse configuration system (unidirectional coupling between two identical systems). Moreover, since in every practical implementation of a communication system, the transmitter and receiver circuits (although identical) operate under slightly different conditions it is essential to consider the case of the mismatch between the parameters of the transmitter and the receiver. In our work we consider the non-autonomous second order non-linear oscillator system presented by G. Mycolaitis et al. in Proceedings of Seventh International Workshop on Nonlinear Dynamics of Electronic Systems [Globally synchronizable non-autonomous chaotic oscillator, Denmark, July 1999, pp. 277-280], which is particularly suitable for digital communications. Binary information is encoded by combining square pulses of two different frequencies selected so that the system is always in the chaotic regime independent of the encoded message. ᭧

showing better security performance than that of the conventional method.

2006 International Conference on Advanced Computing and Communications, 2006

We try to revive the first generation chaotic secure communication scheme by improving the degree of security level, using the concept of mutual chaotic synchronization. This provides additional robustness to secure communication systems designed for quality of service applications. This is aimed at obtaining a system which can generate very long streams of keys to be directly used for one-time stream ciphers (additive masking). The first generation scheme has the advantage of being easily implementable and uses less complex algorithm but have less degree of security. This proposed method is supposed to increase the degree of security level as it is protected against the parameter estimation attacks, which are a major threat to the identical synchronization schemes.

2019

Abstract: In this paper, we study the synchronization of three chaotic T-system with known and unknown parameters. The nonlinear feedback control and adaptive control schemes are used for synchronization with known and unknown parameters respectively. In unknown parameter case, each of systems has two unknown parameters and one known parameter. The stability of synchronization of three system is proved using Lyapunov stability theorem. Also, we use the synchronization of three chaotic systems with unknown parameters in secure communication via masking method. In secure communication, known parameters, unknown parameters, an affine combination of states, and coefficients are used for encryption and decryption. Numerical simulations are shown the effectiveness and feasibility of presented method.

2007

Since chaotic system is extremely sensitive to initial conditions and parameters variations, its application to se-cure communication has provoked a great deal of interest, especially after Carroll and Pecora's outstanding work on successfully synchronizing two chaotic systems ...

Since chaotic signal has a broad spectrum and is noise like, it is suitable for information encryption. Chaotic encryption is superior to key-based encryption as its speed is almost unrelated with key length. This paper presents an improved secure communication algorithm based on a unified system. The algorithm is used for encrypting and decrypting both continuous signals and discrete signals such that of a digital image. Especially, it avoids eigenfrequency assumptions for transmitted signals. Theoretical proof and numerical simulations show its high secure level and feasibility.

The University of Danang - Journal of Science and Technology, 2022

Chaos theory is one of the fields of research that has many practical applications. An important application of chaos in communication is that it can be used for secure communication. To be able to use the chaotic signal in communication, we need to synchronize the chaotic signal between the receiver and the transmitter. In this paper, a sliding mode controller is proposed for global synchronization between two chaotic systems. The interesting point of this controller is that it can help reduce the synchronization time based on the selection of the appropriate gain parameter. This method has also been applied to a secure communication system with chaos masking. Finally, numerical simulations are given to illustrate the effectiveness of the proposed method.

Circuits and Systems II: …, 1993

Abstruct-A circuit implementation of the chaotic Lorenz system is described. The chaotic behavior of the circuit closely matches the results predicted by numerical experiments. Using the concept of synchronized chaotic systems (SCS's), two possible approaches to secure communications are demonstrated with the Lorenz circuit implemented in both the transmitter and receiver. In the first approach, a chaotic masking signal is added at the transmitter to the message, and at the receiver, the masking is regenerated and subtracted from the received signal. The second approach utilizes modulation of the coefficients of the chaotic system in the transmitter and corresponding detection of synchronization error in the receiver to transmit binary-valued bit streams.

Physics Letters A, 2010

A new method for secure information transmission based on generalized synchronization is proposed. The principal advantage of it is a remarkable stability to noise. To reveal this peculiarity of the proposed method the effectiveness of the detection of the information signal from the transmitted one in the presence of noise in the communication channel is examined both for the proposed scheme and for the schemes of chaotic communication known already. The main ideas of the proposed method are illustrated by the example of coupled Rössler systems used both transmitter and receiver.

International Journal of Bifurcation and Chaos, 2005

In this article, the secure transmission of data is being realized on the basis of the synchronization of two chaotic systems. The transmitted signal is only the sign of a projection of the state. This has the advantage of making the transmission not very sensitive to the noises of transmission and the attenuation of the transmitted signal without using a VCO (Voltage Control Oscillatory) into the transmitter and the receiver. It should be noted that for the considered type of chaotic system, the traditional conditions of observability and linearization by injection of outputs are not checked. Here, we can only carry out an estimator.