This work presents several classes of messages that lead to data leakage during modular exponentiation. Such messages allow for the recovery of the entire secret exponent with a single power measurement. We show that padding schemes as defined by industry standards such as PKCS#1 and ANSI x9.31 are vulnerable to side-channel attacks since they meet the characteristics defined by our classes. Th...

In this paper we propose new methods to blind exponents used in RSA and in elliptic curves based algorithms. Due to classical differential power analysis (DPA and CPA), a lot of countermeasures to protect exponents have been proposed since 1999 Kocher [20] and by Coron [13]. However, these blinding methods present some drawbacks regarding execution time and memory cost. It also got some weaknes...

In recent years, some attacks on cryptographic systems have been deviced, exploiting the leakage of information through so-called “side channels”. When a real-life device is performing a coding or decoding procedure, one can measure quantities such as the time employed, the profile of power consumption, the contents of a particular memory cell. If the algorithm is known, this information can ge...

Secret key recovery from weak side channel leakage is always a challenge in the presence of standard counter-measures. The use of randomised exponent recodings in RSA or ECC means that, over multiple re-uses of a key, operations which correspond to a given key bit are not aligned in the traces. This enhances the difficulties because traces cannot be averaged to improve the signal-to-noise ratio...

introduction: there are several methods for evaluating microleakage in dentistry, for example dye or bacterial leakage, electro-chemical methods, radioisotope labeling and fluid filtration. the purpose of this study was to assemble the fluid filtration system for quantitative evaluation of microleakage in dental materials. materials and methods: the roots were connected to a tube filled with an...

High voltage gradient ZnO-based thick film varistors were fabricated by low-temperature sintering. The effect of sintering temperature on electrical properties of thick film varistors was investigated. The voltage gradient of thick film varistors increased significantly to 3159.4 V/mm after sintering at 725°C for 30 min. The small average grain size with good grain boundaries was the origin for...

Alginate based mineral oil entrapped emulsion gel (MOEG) buoyant beads of domperidone were prepared by emulsion gelation technique. The prepared beads were evaluated for particle size, surface morphology, buoyancy, actual drug content and entrapment efficiency. Effect of different oils (castor oil, olive oil and linseed oil) and oil concentrations (10%, 15% and 20%, w/w) on uniformity, homogene...

A closed-form solution for deflections and stresses in an annular thin plate of radially functionally graded material under transverse uniform pressure loading is presented. The small displacement theory of elasticity is assumed in the present work. Young’s modulus of the material is taken in the form of a simple power law to vary in the radial direction with an arbitrary exponent showing heter...

The neutron density is one of the most important dynamical parameters in a reactor. It is directly related to the control and stability of the reactor power. Any change in applied reactivity and some of dynamical parameters in the reactor causes a change in the neutron density. Lyapunov exponent method is a powerful tool for investigating the range of stability and the transient behavior of the...