71,025 research outputs found
On the Design of Perceptual MPEG-Video Encryption Algorithms
In this paper, some existing perceptual encryption algorithms of MPEG videos
are reviewed and some problems, especially security defects of two recently
proposed MPEG-video perceptual encryption schemes, are pointed out. Then, a
simpler and more effective design is suggested, which selectively encrypts
fixed-length codewords (FLC) in MPEG-video bitstreams under the control of
three perceptibility factors. The proposed design is actually an encryption
configuration that can work with any stream cipher or block cipher. Compared
with the previously-proposed schemes, the new design provides more useful
features, such as strict size-preservation, on-the-fly encryption and multiple
perceptibility, which make it possible to support more applications with
different requirements. In addition, four different measures are suggested to
provide better security against known/chosen-plaintext attacks.Comment: 10 pages, 5 figures, IEEEtran.cl
Image Encryption Based on Diffusion and Multiple Chaotic Maps
In the recent world, security is a prime important issue, and encryption is
one of the best alternative way to ensure security. More over, there are many
image encryption schemes have been proposed, each one of them has its own
strength and weakness. This paper presents a new algorithm for the image
encryption/decryption scheme. This paper is devoted to provide a secured image
encryption technique using multiple chaotic based circular mapping. In this
paper, first, a pair of sub keys is given by using chaotic logistic maps.
Second, the image is encrypted using logistic map sub key and in its
transformation leads to diffusion process. Third, sub keys are generated by
four different chaotic maps. Based on the initial conditions, each map may
produce various random numbers from various orbits of the maps. Among those
random numbers, a particular number and from a particular orbit are selected as
a key for the encryption algorithm. Based on the key, a binary sequence is
generated to control the encryption algorithm. The input image of 2-D is
transformed into a 1- D array by using two different scanning pattern (raster
and Zigzag) and then divided into various sub blocks. Then the position
permutation and value permutation is applied to each binary matrix based on
multiple chaos maps. Finally the receiver uses the same sub keys to decrypt the
encrypted images. The salient features of the proposed image encryption method
are loss-less, good peak signal-to-noise ratio (PSNR), Symmetric key
encryption, less cross correlation, very large number of secret keys, and
key-dependent pixel value replacement.Comment: 14 pages,9 figures and 5 tables;
http://airccse.org/journal/jnsa11_current.html, 201
Security Through Amnesia: A Software-Based Solution to the Cold Boot Attack on Disk Encryption
Disk encryption has become an important security measure for a multitude of
clients, including governments, corporations, activists, security-conscious
professionals, and privacy-conscious individuals. Unfortunately, recent
research has discovered an effective side channel attack against any disk
mounted by a running machine\cite{princetonattack}. This attack, known as the
cold boot attack, is effective against any mounted volume using
state-of-the-art disk encryption, is relatively simple to perform for an
attacker with even rudimentary technical knowledge and training, and is
applicable to exactly the scenario against which disk encryption is primarily
supposed to defend: an adversary with physical access. To our knowledge, no
effective software-based countermeasure to this attack supporting multiple
encryption keys has yet been articulated in the literature. Moreover, since no
proposed solution has been implemented in publicly available software, all
general-purpose machines using disk encryption remain vulnerable. We present
Loop-Amnesia, a kernel-based disk encryption mechanism implementing a novel
technique to eliminate vulnerability to the cold boot attack. We offer
theoretical justification of Loop-Amnesia's invulnerability to the attack,
verify that our implementation is not vulnerable in practice, and present
measurements showing our impact on I/O accesses to the encrypted disk is
limited to a slowdown of approximately 2x. Loop-Amnesia is written for x86-64,
but our technique is applicable to other register-based architectures. We base
our work on loop-AES, a state-of-the-art open source disk encryption package
for Linux.Comment: 13 pages, 4 figure
Encryption of Covert Information into Multiple Statistical Distributions
A novel strategy to encrypt covert information (code) via unitary projections
into the null spaces of ill-conditioned eigenstructures of multiple host
statistical distributions, inferred from incomplete constraints, is presented.
The host pdf's are inferred using the maximum entropy principle. The projection
of the covert information is dependent upon the pdf's of the host statistical
distributions. The security of the encryption/decryption strategy is based on
the extreme instability of the encoding process. A self-consistent procedure to
derive keys for both symmetric and asymmetric cryptography is presented. The
advantages of using a multiple pdf model to achieve encryption of covert
information are briefly highlighted. Numerical simulations exemplify the
efficacy of the model.Comment: 18 pages, 4 figures. Three sentences expanded to emphasize detail.
Typos correcte
Block encryption of quantum messages
In modern cryptography, block encryption is a fundamental cryptographic
primitive. However, it is impossible for block encryption to achieve the same
security as one-time pad. Quantum mechanics has changed the modern
cryptography, and lots of researches have shown that quantum cryptography can
outperform the limitation of traditional cryptography.
This article proposes a new constructive mode for private quantum encryption,
named , which is a very simple method to construct quantum
encryption from classical primitive. Based on mode, we
construct a quantum block encryption (QBE) scheme from pseudorandom functions.
If the pseudorandom functions are standard secure, our scheme is
indistinguishable encryption under chosen plaintext attack. If the pseudorandom
functions are permutation on the key space, our scheme can achieve perfect
security. In our scheme, the key can be reused and the randomness cannot, so a
-bit key can be used in an exponential number of encryptions, where the
randomness will be refreshed in each time of encryption. Thus -bit key can
perfectly encrypt qubits, and the perfect secrecy would not be broken
if the -bit key is reused for only exponential times.
Comparing with quantum one-time pad (QOTP), our scheme can be the same secure
as QOTP, and the secret key can be reused (no matter whether the eavesdropping
exists or not). Thus, the limitation of perfectly secure encryption (Shannon's
theory) is broken in the quantum setting. Moreover, our scheme can be viewed as
a positive answer to the open problem in quantum cryptography "how to
unconditionally reuse or recycle the whole key of private-key quantum
encryption". In order to physically implement the QBE scheme, we only need to
implement two kinds of single-qubit gates (Pauli gate and Hadamard gate),
so it is within reach of current quantum technology.Comment: 13 pages, 1 figure. Prior version appears in
eprint.iacr.org(iacr/2017/1247). This version adds some analysis about
multiple-message encryption, and modifies lots of contents. There are no
changes about the fundamental result
Generic key Generation Algorithm using Weighted Graphs
Data is of all sorts, ranging from all pertaining entertainment to national defense. There is a highly pressing need in today’s “online” world to maintain confidentiality of data. The cost of revelation of highly sensitized data far exceeds the cost to establish and maintain security measures. Disclosure of confidential data leads to cataclysmic losses to the victim enterprise. Not just a company’s finances, even national security could be threatened by lax security. In order to keep our information discreet, we need to be on top of things by implementation of stronger encryption systems. On referring several encryption algorithms it was found that most encryption algorithms had a common trait that they used a single fixed key for entire data encryption. Modifying this peculiarity, our key generation algorithm strengthens any encryption algorithm by generating multiple keys
A novel efficient multiple encryption algorithm for real time images
In this study, we propose an innovative image encryption Techniques based on four different image encryption Algorithm. Our methodology integrates scrambling followed by Symmetric and Asymmetric Encryption Techniques, to make the image meaningless or disordered to enhance the ability to confront attack and in turn improve the security. This paper mainly focused on the multiple encryption Techniques with multiple keys on a single image by dividing it into four blocks. So instead of using one Encryption method a combination of four different Encryption Algorithm can make our image more secure. The Encryption is done first by using DNA as secret key, second by using RSA, third by DES and fourth by Chebyshev. The pros and cons for all the Encryption methods are discussed here. Proposed methodology can strongly encrypt the images for the purpose of storing images and transmitting them over the Internet. There are two major benefits related with this system. The first benefit is the use of Different Algorithm with different keys. The second benefit is that even though we are using four different Algorithm for a single image, the time taken for encryption and decryption is few seconds only. Our method is methodically checked, and it shows an exceptionally high level of security with very good image quality
- …