scholarly journals Speech Encryption Algorithm Based on Nonorthogonal Quantum State with Hyperchaotic Keystreams

2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
F. J. Farsana ◽  
K. Gopakumar
Keyword(s):  
Quantum State ◽  
Initial Conditions ◽  
Encryption Algorithm ◽  
Hadamard Transform ◽  
Hyperchaotic System ◽  
Classical Domain ◽  
Quantum Domain ◽  
Novel Approach ◽  
Speech Encryption ◽  
Shared Networks

With the advancement in modern computational technologies like cloud computing, there has been tremendous growth in the field of data processing and encryption technologies. In this contest there is an increasing demand for successful storage of the data in the encrypted domain to avoid the possibility of data breach in shared networks. In this paper, a novel approach for speech encryption algorithm based on quantum chaotic system is designed. In the proposed method, classical bits of the speech samples are initially encoded in nonorthogonal quantum state by the secret polarizing angle. In the quantum domain, encoded speech samples are subjected to bit-flip operation according to the Controlled–NOT gate followed by Hadamard transform. Complete superposition of the quantum state in both Hadamard and standard basis is achieved through Hadamard transform. Control bits for C-NOT gate as well as Hadamard gate are generated with a modified Lu˙-hyperchaotic system. Secret nonorthogonal rotation angles and initial conditions of the hyperchaotic system are the keys used to ensure the security of the proposed algorithm. The computational complexity of the proposed algorithm has been analysed both in quantum domain and classical domain. Numerical simulation carried out based on the above principle showed that the proposed speech encryption algorithm has wider keyspace, higher key sensitivity and robust against various differential and statistical cryptographic attacks.

A Novel Approach for Designing Dynamical S-Boxes Using Hyperchaotic System

2012 ◽  
Vol 6 (1) ◽  
pp. 100-119 ◽  
Author(s):  
Jun Peng ◽  
Du Zhang ◽  
Xiaofeng Liao
Keyword(s):  
Lorenz System ◽  
Initial Conditions ◽  
Hyperchaotic System ◽  
Differential Approximation ◽  
Novel Approach ◽  
Substitution Boxes ◽  
Hyperchaotic Lorenz System ◽  
Digital Image Encryption ◽  
Image Encryption Algorithm ◽  
Independence Criterion

In the information security field, the substitution boxes (S-boxes) have been extensively used in many cryptographic systems. This paper presents a novel approach for generating dynamically cryptographically S-boxes using a four-dimensional hyperchaotic Lorenz system. Within the algorithm, the initial condition is employed to drive the hyper-chaotic system to generate a chaotic sequence which is used to construct a chaotic key-dependent S-box. With different system initial conditions, many of distinct S-boxes can be obtained dynamically. Some cryptographic properties for a good S-box such as bijection, nonlinearity, SAC (Strict Avalanche Criterion), BIC (Bit Independence Criterion), and differential approximation probability are found to hold in the obtained S-boxes. The analytic results indicated that all the criteria for designing strong S-boxes can be achieved. The comparison of the proposed method for generating S-boxes with other chaos-based schemes indicates that our S-boxes have a better performance with respect to some properties. Finally, the authors give an example of a digital image encryption algorithm using their S-box and the results of image statistical analysis show that the algorithm has the desirable cryptographic properties.

scholarly journals Image Encryption Algorithm Based on a Novel Six-Dimensional Hyper- Chaotic System

2020 ◽  
Vol 31 (1) ◽  
pp. 54
Author(s):  
Sadiq A. Mehdi ◽  
Zaydon Latif Ali
Keyword(s):  
Image Encryption ◽  
Chaotic System ◽  
Data Security ◽  
Initial Conditions ◽  
Multimedia Data ◽  
Encryption Algorithm ◽  
Hyperchaotic System ◽  
Secret Key ◽  
Promising Alternative ◽  
Multimedia Data Security

Due to the rapid evaluation in the field of communications and multimedia and the increasing use of the Internet, multimedia data security has become very urgent. of the best alternative way to achieve multimedia data security is encryption, which prevents unauthorized entities from accessing confidential data. In recent years, the chaotic system of image encryption becomes an efficient way to encrypt images due to its high security. It has certain special properties like sensitivity to initial conditions, and control parameters, pseudorandom, ergodicity, and non-convergence, etc. chaotic dynamics systems became a promising alternative to traditional encryption algorithms. In this paper, This paper presents a new algorithm for the image encryption/decryption scheme depended on a  novel six-dimensional hyper-chaotic system to achieve a high level of security, the chaotic sequence generated from system employ for permutation and diffusion the original image to create an encrypted image.  The performance of  the algorithm has been analyzed through analyzes statistical such  as  Histogram  Analysis,  Correlation  Coefficient  Analysis,  Information  Entropy Analysis, Key Space Analysis, Key Sensitivity Analysis, Number of Pixels Change Rate (NPCR), Unified Average Changing Intensity (UACI), Peak Signal to Noise Ratio, The experimental results show that the algorithm has good encryption performance, large keyspace equals to  and the high sensitivity  for  small  changes  in  secret key  which makes  the  algorithm  immune  to Brute  force  attacks,  and  it  can  resist  the  statistical  attacks, therefore,  the presented  encryption  algorithm depends on a novel hyperchaotic system is more secure against the statistical and differential attacks.

scholarly journals Non-Linear Hopped Chaos Parameters-Based Image Encryption Algorithm Using Histogram Equalization

Entropy ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. 535
Author(s):  
Karim H. Moussa ◽  
Ahmed I. El Naggary ◽  
Heba G. Mohamed
Keyword(s):  
Image Encryption ◽  
Initial Conditions ◽  
Signal To Noise Ratio ◽  
Chaotic Map ◽  
Histogram Equalization ◽  
Encryption Algorithm ◽  
Multimedia Contents ◽  
Encryption Schemes ◽  
Change Intensity ◽  
Increasing Demand

Multimedia wireless communications have rapidly developed over the years. Accordingly, an increasing demand for more secured media transmission is required to protect multimedia contents. Image encryption schemes have been proposed over the years, but the most secure and reliable schemes are those based on chaotic maps, due to the intrinsic features in such kinds of multimedia contents regarding the pixels’ high correlation and data handling capabilities. The novel proposed encryption algorithm introduced in this article is based on a 3D hopping chaotic map instead of fixed chaotic logistic maps. The non-linearity behavior of the proposed algorithm, in terms of both position permutation and value transformation, results in a more secured encryption algorithm due to its non-convergence, non-periodicity, and sensitivity to the applied initial conditions. Several statistical and analytical tests such as entropy, correlation, key sensitivity, key space, peak signal-to-noise ratio, noise attacks, number of pixels changing rate (NPCR), unified average change intensity randomness (UACI), and others tests were applied to measure the strength of the proposed encryption scheme. The obtained results prove that the proposed scheme is very robust against different cryptography attacks compared to similar encryption schemes.

scholarly journals Vector Map Encryption Algorithm Based on Double Random Position Permutation Strategy

2021 ◽  
Vol 10 (5) ◽  
pp. 311
Author(s):  
Xiaolong Wang ◽  
Haowen Yan ◽  
Liming Zhang
Keyword(s):  
Encryption Algorithm ◽  
Hyperchaotic System ◽  
Secret Key ◽  
Vector Map ◽  
Coordinate Position ◽  
Random Position ◽  
One To One ◽  
Map Objects ◽  
Geographic Information Sciences ◽  
The Relationship

Encryption of vector maps, used for copyright protection, is of importance in the community of geographic information sciences. However, some studies adopt one-to-one mapping to scramble vertices and permutate the coordinates one by one according to the coordinate position in a plain map. An attacker can easily obtain the key values by analyzing the relationship between the cipher vector map and the plain vector map, which will lead to the ineffectiveness of the scrambling operation. To solve the problem, a vector map encryption algorithm based on a double random position permutation strategy is proposed in this paper. First, the secret key sequence is generated using a four-dimensional quadratic autonomous hyperchaotic system. Then, all coordinates of the vector map are encrypted using the strategy of double random position permutation. Lastly, the encrypted coordinates are reorganized according to the vector map structure to obtain the cipher map. Experimental results show that: (1) one-to-one mapping between the plain vector map and cipher vector map is prevented from happening; (2) scrambling encryption between different map objects is achieved; (3) hackers cannot obtain the permutation key value by analyzing the pairs of the plain map and cipher map.

Hidden Extreme Multistability, Antimonotonicity and Offset Boosting Control in a Novel Fractional-Order Hyperchaotic System Without Equilibrium

2018 ◽  
Vol 28 (13) ◽  
pp. 1850167 ◽  
Author(s):  
Sen Zhang ◽  
Yicheng Zeng ◽  
Zhijun Li ◽  
Chengyi Zhou
Keyword(s):  
Fractional Order ◽  
Initial Conditions ◽  
State Feedback Control ◽  
Hyperchaotic System ◽  
Hidden Attractors ◽  
System Parameters ◽  
Offset Boosting ◽  
Extreme Multistability ◽  
Hidden Extreme Multistability ◽  
New System

Recently, the notion of hidden extreme multistability and hidden attractors is very attractive in chaos theory and nonlinear dynamics. In this paper, by utilizing a simple state feedback control technique, a novel 4D fractional-order hyperchaotic system is introduced. Of particular interest is that this new system has no equilibrium, which indicates that its attractors are all hidden and thus Shil’nikov method cannot be applied to prove the existence of chaos for lacking hetero-clinic or homo-clinic orbits. Compared with other fractional-order chaotic or hyperchaotic systems, this new system possesses three unique and remarkable features: (i) The amazing and interesting phenomenon of the coexistence of infinitely many hidden attractors with respect to same system parameters and different initial conditions is observed, meaning that hidden extreme multistability arises. (ii) By varying the initial conditions and selecting appropriate system parameters, the striking phenomenon of antimonotonicity is first discovered, especially in such a fractional-order hyperchaotic system without equilibrium. (iii) An attractive special feature of the convenience of offset boosting control of the system is also revealed. The complex and rich hidden dynamic behaviors of this system are investigated by using conventional nonlinear analysis tools, including equilibrium stability, phase portraits, bifurcation diagram, Lyapunov exponents, spectral entropy complexity, and so on. Furthermore, a hardware electronic circuit is designed and implemented. The hardware experimental results and the numerical simulations of the same system on the Matlab platform are well consistent with each other, which demonstrates the feasibility of this new fractional-order hyperchaotic system.

scholarly journals An Efficient Method of Image Encryption Using Rossler Chaotic System

2021 ◽  
Vol 10 (2) ◽  
pp. 11
Author(s):  
Yasir Ahmed Hamza ◽  
Marwan Dahar Omer
Keyword(s):  
Image Encryption ◽  
Chaotic System ◽  
Initial Conditions ◽  
Computation Time ◽  
Encryption Algorithm ◽  
Brute Force ◽  
Symmetric Encryption ◽  
New Approach ◽  
System Parameters ◽  
Plain Image

In this study, a new approach of image encryption has been proposed. This method is depends on the symmetric encryption algorithm RC4 and Rossler chaotic system. Firstly, the encryption key is employed to ciphering a plain image using RC4 and obtains a ciphered-image. Then, the same key is used to generate the initial conditions of the Rossler system. The system parameters and the initial conditions are used as the inputs for Rossler chaotic system to generate the 2-dimensional array of random values. The resulted array is XORed with the ciphered-image to obtain the final encrypted-image. Based on the experimental results, the proposed method has achieved high security and less computation time. Also, the proposed method can be resisted attacks like (statistical, brute-force, and differential).

scholarly journals Optomechanical state reconstruction and nonclassicality verification beyond the resolved-sideband regime

Quantum ◽  
2019 ◽  
Vol 3 ◽  
pp. 125 ◽  
Author(s):  
Farid Shahandeh ◽  
Martin Ringbauer
Keyword(s):  
Quantum State ◽  
Tomographic Reconstruction ◽  
Mechanical Systems ◽  
Mechanical Resonators ◽  
Optical Cavities ◽  
Novel Approach ◽  
State Transfer ◽  
Wide Range ◽  
Coherent Pulse ◽  
Quantum Optomechanics

Quantum optomechanics uses optical means to generate and manipulate quantum states of motion of mechanical resonators. This provides an intriguing platform for the study of fundamental physics and the development of novel quantum devices. Yet, the challenge of reconstructing and verifying the quantum state of mechanical systems has remained a major roadblock in the field. Here, we present a novel approach that allows for tomographic reconstruction of the quantum state of a mechanical system without the need for extremely high quality optical cavities. We show that, without relying on the usual state transfer presumption between light an mechanics, the full optomechanical Hamiltonian can be exploited to imprint mechanical tomograms on a strong optical coherent pulse, which can then be read out using well-established techniques. Furthermore, with only a small number of measurements, our method can be used to witness nonclassical features of mechanical systems without requiring full tomography. By relaxing the experimental requirements, our technique thus opens a feasible route towards verifying the quantum state of mechanical resonators and their nonclassical behaviour in a wide range of optomechanical systems.

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