1,885 research outputs found
Yet Another Pseudorandom Number Generator
We propose a novel pseudorandom number generator based on R\"ossler attractor
and bent Boolean function. We estimated the output bits properties by number of
statistical tests. The results of the cryptanalysis show that the new
pseudorandom number generation scheme provides a high level of data security.Comment: 5 pages, 7 figures; to be published in International Journal of
Electronics and Telecommunications, vol.63, no.
Cryptographic requirements for chaotic secure communications
In recent years, a great amount of secure communications systems based on
chaotic synchronization have been published. Most of the proposed schemes fail
to explain a number of features of fundamental importance to all cryptosystems,
such as key definition, characterization, and generation. As a consequence, the
proposed ciphers are difficult to realize in practice with a reasonable degree
of security. Likewise, they are seldom accompanied by a security analysis.
Thus, it is hard for the reader to have a hint about their security. In this
work we provide a set of guidelines that every new cryptosystems would benefit
from adhering to. The proposed guidelines address these two main gaps, i.e.,
correct key management and security analysis, to help new cryptosystems be
presented in a more rigorous cryptographic way. Also some recommendations are
offered regarding some practical aspects of communications, such as channel
noise, limited bandwith, and attenuation.Comment: 13 pages, 3 figure
Applications of tripled chaotic maps in cryptography
Security of information has become a major issue during the last decades. New
algorithms based on chaotic maps were suggested for protection of different
types of multimedia data, especially digital images and videos in this period.
However, many of them fundamentally were flawed by a lack of robustness and
security. For getting higher security and higher complexity, in the current
paper, we introduce a new kind of symmetric key block cipher algorithm that is
based on \emph{tripled chaotic maps}. In this algorithm, the utilization of two
coupling parameters, as well as the increased complexity of the cryptosystem,
make a contribution to the development of cryptosystem with higher security. In
order to increase the security of the proposed algorithm, the size of key space
and the computational complexity of the coupling parameters should be increased
as well. Both the theoretical and experimental results state that the proposed
algorithm has many capabilities such as acceptable speed and complexity in the
algorithm due to the existence of two coupling parameter and high security.
Note that the ciphertext has a flat distribution and has the same size as the
plaintext. Therefore, it is suitable for practical use in secure
communications.Comment: 21 pages, 10 figure
Synchronization of spatiotemporal semiconductor lasers and its application in color image encryption
Optical chaos is a topic of current research characterized by
high-dimensional nonlinearity which is attributed to the delay-induced
dynamics, high bandwidth and easy modular implementation of optical feedback.
In light of these facts, which adds enough confusion and diffusion properties
for secure communications, we explore the synchronization phenomena in
spatiotemporal semiconductor laser systems. The novel system is used in a
two-phase colored image encryption process. The high-dimensional chaotic
attractor generated by the system produces a completely randomized chaotic time
series, which is ideal in the secure encoding of messages. The scheme thus
illustrated is a two-phase encryption method, which provides sufficiently high
confusion and diffusion properties of chaotic cryptosystem employed with unique
data sets of processed chaotic sequences. In this novel method of cryptography,
the chaotic phase masks are represented as images using the chaotic sequences
as the elements of the image. The scheme drastically permutes the positions of
the picture elements. The next additional layer of security further alters the
statistical information of the original image to a great extent along the
three-color planes. The intermediate results during encryption demonstrate the
infeasibility for an unauthorized user to decipher the cipher image. Exhaustive
statistical tests conducted validate that the scheme is robust against noise
and resistant to common attacks due to the double shield of encryption and the
infinite dimensionality of the relevant system of partial differential
equations.Comment: 20 pages, 11 figures; Article in press, Optics Communications (2011
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