16,866 research outputs found
The Hush Cryptosystem
In this paper we describe a new cryptosystem we call "The Hush Cryptosystem"
for hiding encrypted data in innocent Arabic sentences. The main purpose of
this cryptosystem is to fool observer-supporting software into thinking that
the encrypted data is not encrypted at all. We employ a modified Word
Substitution Method known as the Grammatical Substitution Method in our
cryptosystem. We also make use of Hidden Markov Models. We test our
cryptosystem using a computer program written in the Java Programming Language.
Finally, we test the output of our cryptosystem using statistical tests.Comment: 7 pages. 5 figures. Appeared in the 2nd International Conference on
Security of Information and Networks (SIN 2009), North Cyprus, Turkey;
Proceedings of the 2nd International Conference on Security of Information
and Networks (SIN 2009), North Cyprus, Turke
CacheZoom: How SGX Amplifies The Power of Cache Attacks
In modern computing environments, hardware resources are commonly shared, and
parallel computation is widely used. Parallel tasks can cause privacy and
security problems if proper isolation is not enforced. Intel proposed SGX to
create a trusted execution environment within the processor. SGX relies on the
hardware, and claims runtime protection even if the OS and other software
components are malicious. However, SGX disregards side-channel attacks. We
introduce a powerful cache side-channel attack that provides system adversaries
a high resolution channel. Our attack tool named CacheZoom is able to virtually
track all memory accesses of SGX enclaves with high spatial and temporal
precision. As proof of concept, we demonstrate AES key recovery attacks on
commonly used implementations including those that were believed to be
resistant in previous scenarios. Our results show that SGX cannot protect
critical data sensitive computations, and efficient AES key recovery is
possible in a practical environment. In contrast to previous works which
require hundreds of measurements, this is the first cache side-channel attack
on a real system that can recover AES keys with a minimal number of
measurements. We can successfully recover AES keys from T-Table based
implementations with as few as ten measurements.Comment: Accepted at Conference on Cryptographic Hardware and Embedded Systems
(CHES '17
A Polynomial Description of the Rijndael Advanced Encryption Standard
The paper gives a polynomial description of the Rijndael Advanced Encryption
Standard recently adopted by the National Institute of Standards and
Technology. Special attention is given to the structure of the S-Box.Comment: 12 pages, LaTe
Optimized Compressed Sensing Matrix Design for Noisy Communication Channels
We investigate a power-constrained sensing matrix design problem for a
compressed sensing framework. We adopt a mean square error (MSE) performance
criterion for sparse source reconstruction in a system where the
source-to-sensor channel and the sensor-to-decoder communication channel are
noisy. Our proposed sensing matrix design procedure relies upon minimizing a
lower-bound on the MSE. Under certain conditions, we derive closed-form
solutions to the optimization problem. Through numerical experiments, by
applying practical sparse reconstruction algorithms, we show the strength of
the proposed scheme by comparing it with other relevant methods. We discuss the
computational complexity of our design method, and develop an equivalent
stochastic optimization method to the problem of interest that can be solved
approximately with a significantly less computational burden. We illustrate
that the low-complexity method still outperforms the popular competing methods.Comment: Submitted to IEEE ICC 2015 (EXTENDED VERSION
AES-CBC Software Execution Optimization
With the proliferation of high-speed wireless networking, the necessity for
efficient, robust and secure encryption modes is ever increasing. But,
cryptography is primarily a computationally intensive process. This paper
investigates the performance and efficiency of IEEE 802.11i approved Advanced
Encryption Standard (AES)-Rijndael ciphering/deciphering software in Cipher
Block Chaining (CBC) mode. Simulations are used to analyse the speed, resource
consumption and robustness of AES-CBC to investigate its viability for image
encryption usage on common low power devices. The detailed results presented in
this paper provide a basis for performance estimation of AES cryptosystems
implemented on wireless devices. The use of optimized AES-CBC software
implementation gives a superior encryption speed performance by 12 - 30%, but
at the cost of twice more memory for code size.Comment: 8 pages, IEEE 200
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