1,548 research outputs found
On the security of a new image encryption scheme based on chaotic map lattices
This paper reports a detailed cryptanalysis of a recently proposed encryption
scheme based on the logistic map. Some problems are emphasized concerning the
key space definition and the implementation of the cryptosystem using
floating-point operations. It is also shown how it is possible to reduce
considerably the key space through a ciphertext-only attack. Moreover, a timing
attack allows the estimation of part of the key due to the existent
relationship between this part of the key and the encryption/decryption time.
As a result, the main features of the cryptosystem do not satisfy the demands
of secure communications. Some hints are offered to improve the cryptosystem
under study according to those requirements.Comment: 8 pages, 8 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
A Novel Image Encryption Using an Integration Technique of Blocks Rotation Based on the Magic Cube and the AES Algorithm
In recent years, several encryption algorithms have been proposed to protect
digital images from cryptographic attacks. These encryption algorithms
typically use a relatively small key space and therefore, provide safe,
especially if they are of a dimension. In this paper proposes an encryption
algorithm for a new image protection scheme based on the rotation of the faces
of a Magic Cube. The original image is divided into six sub-images and these
sub-images are divided amongst a number of blocks and attached to the faces of
a Magic Cube. The faces are then scrambled using rotation of the Magic Cube.
Then the rotated image is fed to the AES algorithm which is applied to the
pixels of the image to encrypt the scrambled image. Finally, experimental
results and security analysis show that the proposed image encryption scheme
not only encrypts the picture to achieve perfect hiding, but the algorithm can
also withstand exhaustive, statistical and differential attacks
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