Enhancing chaos in multistability regions of Duffing map for an asymmetric image encryption algorithm

We investigate the dynamics of a two-dimensional chaotic Duffing map which exhibits the occurrence of coexisting chaotic attractors as well as periodic orbits with a typical set of system parameters. Such unusual behaviors in low-dimensional maps is inadmissible especially in the applications of chaos based cryptography. To this end, the Sine-Cosine chaotification technique is used to propose a modified Duffing map in enhancing its chaos complexity in the multistable regions. Based on the enhanced Duffing map, a new asymmetric image encryption algorithm is developed with the principles of confusion and diffusion. While in the former, hyperchaotic sequences are generated for scrambling of plain-image pixels, the latter is accomplished by the elliptic curves, S-box and hyperchaotic sequences. Simulation results and security analysis reveal that the proposed encryption algorithm can effectively encrypt and decrypt various kinds of digital images with a high-level security.Comment: 15 pages, 15 figure

Characterizing noise-induced chaos and multifractality of a finance system

In this article, noise induced chaos is investigated for a finance system. To characterize chaotic paradigm, period analysis is done with the variation of a parameter and noise strength. Later on, chaos has been quantified by 0–1 tests under the same variation. A phase space analysis is also done to investigate the effect of noise on the system dynamics. However, we have noticed that the respective asymptotic dynamics of the deterministic and noise induced chaos are very similar. To classify chaos between noisy and noise free systems, multifractal analysis is then performed. Though the phase spaces are showing similar trajectories, the multifractal analysis confirms more complex dynamics of the noise induced system in compare to the deterministic model. This investigation is an application of multifractal analysis, in case of quantifying chaos