134 research outputs found
From Golden to Unimodular Cryptography
We introduce a natural generalization of the golden cryptography, which uses
general unimodular matrices in place of the traditional Q-matrices, and prove
that it preserves the original error correction properties of the encryption.
Moreover, the additional parameters involved in generating the coding matrices
make this unimodular cryptography resilient to the chosen plaintext attacks
that worked against the golden cryptography. Finally, we show that even the
golden cryptography is generally unable to correct double errors in the same
row of the ciphertext matrix, and offer an additional check number which, if
transmitted, allows for the correction.Comment: 20 pages, no figure
New Key Generation and Encryption Algorithms for Privacy Preservation in Mobile Ad Hoc Networks
Mobile Ad Hoc Networks (MANETs) get widespread applications along with the evolving technologies. However, MANETs are at risk due to the shortage of security mechanisms. In this paper, we propose new algorithms for key generation and encryption for privacy preservation in MANETs. Our key generation algorithm modified Fibonacci sequence by adding scrambling factors to generate random key sequences with required length but incurred low computational overhead, whereas the encryption/decryption algorithm utilizes the One Time Pad (OTP) system by adding scrambling factors for data confidentiality which satisfies the randomness, diffusion, and confusion tests. Simulation of the proposed algorithms was conducted using Matlab and NS-2. Experiment results showed that the proposed algorithms produced random key sequences and random Ciphertexts. Through several tests i.e. speed, correlation and autocorrelation, diffusion, and confusion tests, the simulation result showed the superiority of our algorithms over the other algorithms. For the proof of concept, the proposed algorithms have been simulated in the network simulator, where the result showed that along with the increase of the number of nodes, the throughput of the network increased, while the delay is relatively constant around 6000 ms for 20 up to 70 nodes
Joint watermarking and encryption of color images in the Fibonacci-Haar domain
A novel method for watermarking and ciphering color images, based on the joint use of a key-dependent wavelet transform with a secure cryptographic scheme, is presented. The system allows to watermark encrypted data without requiring the knowledge of the original data and also to cipher watermarked data without damaging the embedded signal. Since different areas of the proposed transform domain are used for encryption and watermarking, the extraction of the hidden information can be performed without deciphering the cover data and it is also possible to decipher watermarked data without removing the watermark. Experimental results show the effectiveness of the proposed scheme
A NOVEL JOINT PERCEPTUAL ENCRYPTION AND WATERMARKING SCHEME (JPEW) WITHIN JPEG FRAMEWORK
Due to the rapid growth in internet and multimedia technologies, many new
commercial applications like video on demand (VOD), pay-per-view and real-time
multimedia broadcast etc, have emerged. To ensure the integrity and confidentiality of
the multimedia content, the content is usually watermarked and then encrypted or vice
versa. If the multimedia content needs to be watermarked and encrypted at the same
time, the watermarking function needs to be performed first followed by encryption
function. Hence, if the watermark needs to be extracted then the multimedia data
needs to be decrypted first followed by extraction of the watermark. This results in
large computational overhead. The solution provided in the literature for this problem
is by using what is called partial encryption, in which media data are partitioned into
two parts - one to be watermarked and the other is encrypted. In addition, some
multimedia applications i.e. video on demand (VOD), Pay-TV, pay-per-view etc,
allow multimedia content preview which involves „perceptual‟ encryption wherein all
or some selected part of the content is, perceptually speaking, distorted with an
encryption key. Up till now no joint perceptual encryption and watermarking scheme
has been proposed in the literature.
In this thesis, a novel Joint Perceptual Encryption and Watermarking (JPEW)
scheme is proposed that is integrated within JPEG standard. The design of JPEW
involves the design and development of both perceptual encryption and watermarking
schemes that are integrated in JPEG and feasible within the „partial‟ encryption
framework. The perceptual encryption scheme exploits the energy distribution of AC
components and DC components bitplanes of continuous-tone images and is carried
out by selectively encrypting these AC coefficients and DC components bitplanes.
The encryption itself is based on a chaos-based permutation reported in an earlier
work. Similarly, in contrast to the traditional watermarking schemes, the proposed
watermarking scheme makes use of DC component of the image and it is carried out
by selectively substituting certain bitplanes of DC components with watermark bits.
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Apart from the aforesaid JPEW, additional perceptual encryption scheme, integrated
in JPEG, has also been proposed. The scheme is outside of joint framework and
implements perceptual encryption on region of interest (ROI) by scrambling the DCT
blocks of the chosen ROI.
The performances of both, perceptual encryption and watermarking schemes are
evaluated and compared with Quantization Index modulation (QIM) based
watermarking scheme and reversible Histogram Spreading (RHS) based perceptual
encryption scheme. The results show that the proposed watermarking scheme is
imperceptible and robust, and suitable for authentication. Similarly, the proposed
perceptual encryption scheme outperforms the RHS based scheme in terms of number
of operations required to achieve a given level of perceptual encryption and provides
control over the amount of perceptual encryption. The overall security of the JPEW
has also been evaluated. Additionally, the performance of proposed separate
perceptual encryption scheme has been thoroughly evaluated in terms of security and
compression efficiency. The scheme is found to be simpler in implementation, have
insignificant effect on compression ratios and provide more options for the selection
of control factor
Performance analysis of gray code number system in image security
The encryption of digital images has become essential since it is vulnerable to interception while being transmitted or stored. A new image encryption algorithm to address the security challenges of traditional image encryption algorithms is presented in this research. The proposed scheme transforms the pixel information of an original image by taking into consideration the pixel location such that two neighboring pixels are processed via two separate algorithms. The proposed scheme utilized the Gray code number system. The experimental results and comparison shows the encrypted images were different from the original images. Also, pixel histogram revealed that the distribution of the plain images and their decrypted images have the same pixel histogram distributions, which means that there is a high correlation between the original images and decrypted images. The scheme also offers strong resistance to statistical attacks
Quad-color image encryption based on Chaos and Fibonacci Q-matrix
The Information technology requires the transmission of daily-life images that may reach to millions or even more. Thus, securing them becomes an urgent matter using the encryption technique. Where, a secret key is used for converting the original image into a noisy one and restoring it back using the same key. Confusion and Diffusion are the wildly used steps in such a technique. Therefore, a new algorithm is presented in this work that uses a fusion, segmentation, random assembling, hyperchaotic and Fibonacci Q-matrix (FQ-matrix). A novel fusion method is designed for fusing four color images into four different sequences according to their contained information. Then the resulted four images are each divided into four segments to be assembled randomly into one image using a random-key; which confused later using a six-dimensional hyperchaotic system and diffused using the FQ-matrix. The performance and robustness of the proposed algorithm have been computed based on different tests; where it proved its powerful capability in securing the transmitted images
A Newfangled Authentication Protocol Based On Audio Produced Principles
Graphical authentication is more proficient and more securable. An imperative convenience objective for information based authentication frameworks is to bolster client in selecting passwords for higher security in the feeling of being from an extended viable security space. Here we are utilizing x and y directions to pick a photo secret word. Also the photos in x and y directions are changing haphazardly and subsequently it is hard to locate the first picture. In our base paper the methodologies utilized are "Convincing signaled snap focuses"," Cued snap focuses" and "Pass focuses". Primary apparatuses utilized here are pccp, viewport and that is utilized for secret word creation. Viewport methodologies are utilized to significant client picked secret word and secure framework created arbitrary watchword that are hard to recollect. The pccp making a less guessable secret key is the least demanding game-plan. With a specific end goal to dodge "Shoulder surfing" calculation we are going for AES (Advanced encryption standard). In a contemporary mastery, the customary Authentication methodologies like "alphanumeric - usernames and passwords" can't be a versatile secured technique as it make out a critical downsides. It can't be protected and sound from programmers. Graphical passwords are a different option for existing alphanumeric passwords. In Graphical passwords clients click on pictures than sort a long, complex secret key. Exhaustive examination is finished by different analysts proposes that the photo's majority based authentication plans are essentially delicate as client tends to tap on hotspots in the pictures. A hotspot is the picture's territory which is effectively perceived against every single other picture, accordingly making such strategies defenseless. To make greater from the available confirmation, another convention "in light of the sound time stamps" making it hard for the shams to perform mystery. Here is a novel one of a kind answer for graphical validation defining so as To take into account sound time stamps another method for model called "A NEWFANGLED AUTHENTICATION PROTOCOL BASED ON AUDIO PRODUCED PRINCIPLES ". This model calls a sound time stamps and in addition the number of sound timestamps and scramble the secret word with message digest adaptation 5 and making it hard for the gatecrasher to break the watchword there by forcing the more elevated amounts of security to the framework. The gatecrasher can't get the time stamps and additionally check of time stamps and making this strategy more secure, dependable and difficult to figure
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