The authors propose a two-timescale version of the one-simulation smoothed functional (SF) algorithm with extra averaging. They also propose the use of a chaotic simple deterministic iterative sequence for generating random samples for averaging. This sequence is used for generating the N independent and identically distributed (i.i.d.), Gaussian random variables in the SF algorithm. The conver...

Nowadays, client authentication in Web applications for each user based on passwords and a statically salts [11, 13, 18, 19]. The aim of this article is to propose random generator of a safe cryptographic salt per session (RGSCS). The interest to introduce this regenerator is to contribute to the evolution of the cryptographic quality of the systems of strong zero knowledge authentication based...

Modern cryptographic protocols require good entropy sources. Unfortunately, many networked devices lack subsystems dedicated to this task, being potentially susceptible to random number generator (RNG) attacks. Yet, most of these systems allow software upgrades and host communication ports, providing the option of a retrofit. This work illustrates how chaotic dynamics can be used to design a su...

In this letter, we present a circuit implementation for the discrete-time zigzag map, which exhibits high speed, low power consumption, and above all resilience to process variations. Circuit parameter variations result in alteration of the chaotic map parameters, such as the slope and the location of the breakpoints in the map, which in turn degrade the randomness of the generated bit sequence...

This paper describes the security weakness of a recently proposed image encryption algorithm based on a logistic-like new chaotic map. We show that the chaotic map’s distribution is far from ideal, thus making it a bad candidate as a pseudo-random stream generator. As a consequence, the images encrypted with this algorithm are shown to be breakable through different attacks of variable complexity.

This paper proposes a chaos-based image encryption scheme with a permutation–diffusion structure. In the proposed scheme, the large permutation with the same size as the plainimage is used to shuffle the positions of image pixels totally. An effective method is also presented to construct the large permutation quickly and easily by combining several small permutations, where small permutations ...

In most published chaos-based communication schemes, the system’s parameters used as a key could be intelligently estimated by a cracker based on the fact that information about the key is contained in the chaotic carrier. In this paper, we will show that the least significant digits (LSDs) of a signal from a chaotic system can be so highly random that the system can be used as a random number ...

THE URGE TO REDUCE THE FORMS of matter to a few elementary constituents must be very ancient. By 450 BCE, Empedocles had already developed or inherited a “standard model” in which everything was composed of four elements—Air, Earth, Fire, and Water. Thinking about the materials available to him, this is not a bad list. But as a predictive model of Nature, it has some obvious shortcomings. Succe...

In this paper we discuss the efficient implementation of pseudochaotic piecewise linear maps with high digitization accuracies, taking the Rényi chaotic map as a reference. The proposed digital architectures are based on a novel algorithmic approach, that uses carry save adders for the nonlinear arithmetic modular calculations arising when computing piecewise linear maps with a finite precision...

The systems of chaotic billiards revealed a well developed chaotic behavior. Despite its good characteristics, these systems have not yet been applied to the cryptography; among the reasons is the difficulty of expressing the equation of particle motion in an explicit form. In this work, we took advantage the properties offered by the random walks and unpredictability of two particles moving in...