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1

Optimization of differential power analysis

Martinasek Z., Macha T., Raso O., Martinasek J., Silhavy P.

Przegląd Elektrotechniczny

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2011

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R. 87, nr 12a

140-144

EN

The article describes the optimization of differential side channel analysis which is often used in differential power analysis. The introductory chapters discusses in great detail the theoretical background of method. The new improvement is proposed, which allow reduction of the required calculations by 73% and it is in the worst case. The method is based on knowledge of the Hamming weight of secret key. Hamming weight of secret key can be determined by adding only one reference measurement of power consumption. The testbed focused on measuring direct emissions was built to verify proposal optimization and experimental verification was carried out.

PL

W artykule opisano metodę optymalizacji różnicowej analizy mocy. Metoda bazuje na znajomości wag Hamminga. Są one określane przez dodanie jednego pomiaru poboru mocy odniesienia.

2

An Application of Thin Layer Chromatography Combined with Optical Densitometry to Quantitative Analysis of Diphenylamine and Its Initial Daughter Reaction Products in Single-Base Propellants Aged under Natural Conditions

Miszczak M.

Central European Journal of Energetic Materials

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2011

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Vol. 8, nr 2

107-116

EN

Thin Layer Chromatography (TLC) was used for the quantitative measurement of the composition of stabilizers used to retard chemical decomposition of single-base (SB) propellants i.e. diphenylamine (DPA), and its initial reaction products due to natural ageing of these propellants under natural (ambient) conditions with test results and certain observations in this matter, are presented. The quantitative determination of DPA and its reaction products was possible by a combination of TLC with the densitometric spectrophotometry technique in the UV detection region. The crucial stage of TLC analytical quantitations was complete extraction of the substances to be analysed from SB propellants nitrocellulose (NC), which was done by rapid dissolution of the SB propellant samples followed by dilution of the solutions obtained to such degree as to make possible TLC separation of the substances to be analysed from the NC "matrix" in which they are "trapped" when the solution is too viscous. Initial chemical changes of DPA in SB propellants resulting in the appearance of DPA initial daughter reaction products such as N-nitroso-DPA, 2-nitro-DPA and 4-nitro-DPA, gave important information on the natural ageing of these homogeneous propellants starting from their very short storage period (some days, weeks or months just after their manufacture) up to long storage lasting even 50 years.

3

Porównawcza ocena testów penetracji wody w papier. Część 3. Wpływ warunków produkcji papieru na wnikanie wody w papier oraz na gęstość optyczną druku

Skowroński J. W., Kryczka M., Pawlak J.

Przegląd Papierniczy

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2010

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R. 66, nr 9

531-536

PL

W niniejszej części przedstawiono wpływ warunków produkcji papieru na naturę wnikania wody w papier oraz jej wpływu na optyczną gęstość druku w metodzie atramentowej.

EN

Part three discusses the impact of paper making variables on nature of paper’s water penetration and its consequences for optical ink’s density of ink-jet printed paper.

4

Porównawcza ocena testów penetracji wody w papier. Część 2. Nowa metodologia testowania wnikania wody w strukturę papieru

Skowroński J. W.

Przegląd Papierniczy

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2010

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R. 66, nr 7

393-398

PL

W pierwszej części niniejszego artykułu (2) wyjaśniono złożoność penetracji wody w strukturę papieru, rozważając takie podstawowe zjawiska, jak: zwilżanie powierzchni włókna, rozprzestrzenianie się wody w porach papieru oraz wewnątrz włókien (pęcznienie). Część druga przedstawia trzy nowe techniki pomiaru wnikania wody w papier, pozwalające na rozróżnienie wnikania w pory papieru od wnikania w pory włókna, oraz pomiar równomierności wnikania wody.

EN

This is part 2 of a series on testing water penetration into paper. Part one (2) outlines the scientific basis of water penetration into paper, interpretation and suitability of presently used tests. Part two will discuss three novel testing techniques allowing to distinguish paper pore penetration from fiber pore penetration and to determine the penetration uniformity.

5

A Novel Method for Testing Propellant Stabilizers

Błądek J., Cudziło S., Pietrzyk S., Wilker S.

Central European Journal of Energetic Materials

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2010

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Vol. 7, nr 4

281-287

EN

In many laboratories, investigations aimed at replacing diphenylamine (DPA, propellant stabilizer) with other, less harmful substances are being carried out. For instance, good effects have been obtained in experiments with triphenylamine (TPA), which cannot produce - due to its structure - carcinogenic nitroso derivatives. In this work, a new, cheap and fast method for testing stabilizing properties of propellant stabilizers that have been used or being developed is presented. It consists in dispersing a stabilizer within silica gel followed by the measurement of the stabilizer transformation kinetics during its nitration with nitrogen oxides. The method combined with thin layer chromatography (TLC) provides a fast evaluation of stabilizing effectiveness.

6

Power equalization of AES FPGA implementation

Strachacki M., Szczepański S.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2010

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Vol. 58, nr 1

125-128

EN

This paper briefly introduces side channel attacks on cryptographic hardware with special emphasis on differential power analysis (DPA). Based on existing countermeasures against DPA, design method combining power equalization for synchronous and combinatorial circuits has been proposed. AES algorithm has been implemented in Xilinx Spartan II-E field programmable gate array (FPGA) device using the standard and power-equalized methods. Power traces for DPA have been collected using XPower tool. Simulation results show that standard AES implementation can be broken after N=500 encryptions, while power-equalized counterpart shows no correlation between power consumption and the cipher key after N=2000 encryptions.

7

Metody sprzętowej implementacji kryptografii odpornej na kryptoanalizę

Strachacki M., Piotrowski R.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

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2007

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T. 14

601-608

PL

W pracy zaprezentowano problematykę kryptoanalizy implementacji sprzętowych bazującej na informacji z kanału bocznego. Opisano rodzaje ataków pasywnych ze szczególnym uwzględnieniem analizy czasowej i analizy poboru mocy. Przedstawiono podstawowe metody zapobiegania atakom. Zaproponowano metodę projektowania wykorzystującą wyrównywanie mocy w asynchronicznych układach kombinacyjnych oraz w układach synchronicznych. Dokonano implementacji algorytmu AES w układzie FPGA Xilinx Spartan II-E w wersji standardowej i zmodyfikowanej. Osiągnięte wyniki symulacji wykazały, że zaproponowana metoda projektowania skutecznie uniemożliwia wykonanie analizy mocy DPA.

EN

The paper presents cryptoanalysis issues of hardware implementations based on side channel information. Kinds of passive attacks are described, especially considering timing analysis and power analysis. Basic countermea-sures against known attacks are shown. New design method based on both asynchronous and synchronous power equalization is proposed. Algorithm AES is chosen for implementation on FPGA Xilinx Spartan II-E device using standard and modified design methodology. Simulation results show that proposed design methodology efficiently prevents from carring out differential power analysis.