A dynamic study with side channel against An Identification Based Encryption

Recently, the side channel keeps the attention of researchers in theory of pairing, since, several studies have been done in this subject and all them have the aim in order to attack the cryptosystems of Identification Based Encryption (IBE) which are integrate into smart cards (more than 80% of those cryptosystems are based on a pairing). The great success and the remarkable development of the cryptography IBE in the recent years and the direct connection of this success to the ability of resistance against any kind of attack, especially the DPA and DFA attacks, leave us to browse saying all the studies of the DPA and DFA attacks applied to a pairing and we have observed that they have no great effect to attack the cryptosystems of IBE. That’s what we will see in this paper. In this work we will illuminate the effect of the DPA attack on a cryptosystems of IBE and we would see on what level we can arrive. Thus in the case where this attack can influence on those cryptosystems, we can present an appropriate counter measures to resist such attack. In the other part we will also propose a convenient counter-measure to defend the attack DFA when the embedding degree is eve

Order-controlled multiple shift SBR2 algorithm for para-hermitian polynomial matrices

In this work we present a new method of controlling the order growth of polynomial matrices in the multiple shift second order sequential best rotation (MS-SBR2) algorithm which has been recently proposed by the authors for calculating the polynomial matrix eigenvalue decomposition (PEVD) for para-Hermitian matrices. In effect, the proposed method introduces a new elementary delay strategy which keeps all the row (column) shifts in the same direction throughout each iteration, which therefore gives us the flexibility to control the polynomial order growth by selecting shifts that ensure non-zero coefficients are kept closer to the zero-lag plane. Simulation results confirm that further order reductions of polynomial matrices can be achieved by using this direction-fixed delay strategy for the MS-SBR2 algorithm

Formulating and solving broadband multichannel problems using matrices of functions

The analysis and design of broadband multichannel systems typically involves convolutive mixing, characterised by matrices of transfer functions. Further, many broadband multichannel problems can be formulated using space-time covariance matrices that include an explicit lag variable and thus cross-correlation sequences as entries. This is in contrast to narrowband challenges, where the problem formulation relies on standard (i.e. constant) matrices; a rich set of solutions that are optimal in various senses can be reached from these formulations by matrix factorisations such as the eigenvalue or singular value decompositions. In order to extend the utility of such linear algebraic techniques to the broadband case, the diagonalisation or factorisation of matrices of functions is key. In this webinar, I will show that such matrices are quite ubiquitous in multichannel signal processing, review some of the theory for their factorisations, and show how with such broadband formulations and solutions directly generalise from their narrowband counterparts. I will sketch out a number of algorithms and illustrate their use in a few example applications such as beamforming, angle or arrival estimation, and signal compaction

Polynomial matrix algebra with applications

[Abstract unavailable

Applications of polynomial eigenvalue decomposition to multichannel broadband signal processing : part 2: eigenvalue decomposition

Multichannel broadband signals arise at the core of many essential military technologies such as radar, sonar and communications, and commercial applications like telecommunications, speech processing, healthcare monitoring and seismic surveillance. The success of these applications often depends on the performance of signal processing tasks such as source localization, channel coding, signal enhancement, and source separation. U n multichannel broadband arrays or convolutively mixed signals, the array signals are generally correlated in time across different sensors. Therefore, the time delays for broadband signals cannot be represented by phase shift alone but need to be explicitly modelled. The relative time shifts are captured using the polynomial space-time covariance matrix, where decorrelation over a range of time shifts can be achieved using a polynomial EVD (PEVD). This tutorial is dedicated to recent developments in PEVD for multichannel broadband signal processing applications. We believe this tutorial and resources, such as code and demo webpages, will motivate and inspire many colleagues and aspiring PhD students working on broadband multichannel signal processing to try PEVD. The applications and demonstrations covered in this proposed tutorial include direction of arrival estimation, beamforming, source identification, weak transient detection, voice activity detection, speech enhancement, source separation and subband coding

Sponge based CCA2 secure asymmetric encryption for arbitrary length message

OAEP and other similar schemes proven secure in Random-Oracle Model require one or more hash functions with output size larger than those of standard hash functions. In this paper, we show that by utilizing popular Sponge constructions in OAEP framework, we can eliminate the need of such hash functions. We provide a new scheme in OAEP framework based on Sponge construction and call our scheme \textit{Sponge based asymmetric encryption padding} (SpAEP). SpAEP is based on 2 functions: Sponge and SpongeWrap, and requires only standard output sizes proposed and standardized for Sponge functions. Our scheme is CCA2 secure for any trapdoor one-way permutation in the ideal permutation model for arbitrary length messages. Our scheme utilizes the versatile Sponge function to enhance the capability and efficiency of the OAEP framework. SpAEP with any trapdoor one-way permutation can also be used as a key encapsulation mechanism and a tag-based key encapsulation mechanism for hybrid encryption. Our scheme SpAEP utilizes the permutation model efficiently in the setting of public key encryption in a novel manner

Post-quantum cryptography

Cryptography is essential for the security of online communication, cars and implanted medical devices. However, many commonly used cryptosystems will be completely broken once large quantum computers exist. Post-quantum cryptography is cryptography under the assumption that the attacker has a large quantum computer; post-quantum cryptosystems strive to remain secure even in this scenario. This relatively young research area has seen some successes in identifying mathematical operations for which quantum algorithms offer little advantage in speed, and then building cryptographic systems around those. The central challenge in post-quantum cryptography is to meet demands for cryptographic usability and flexibility without sacrificing confidence.</p

A Discrete Particle Swarm Optimizer for the Design of Cryptographic Boolean Functions

A Particle Swarm Optimizer for the search of balanced Boolean functions with good cryptographic properties is proposed in this paper. The algorithm is a modified version of the permutation PSO by Hu, Eberhart and Shi which preserves the Hamming weight of the particles positions, coupled with the Hill Climbing method devised by Millan, Clark and Dawson to improve the nonlinearity and deviation from correlation immunity of Boolean functions. The parameters for the PSO velocity equation are tuned by means of two meta-optimization techniques, namely Local Unimodal Sampling (LUS) and Continuous Genetic Algorithms (CGA), finding that CGA produces better results. Using the CGA-evolved parameters, the PSO algorithm is then run on the spaces of Boolean functions from $n=7$ to $n=12$ variables. The results of the experiments are reported, observing that this new PSO algorithm generates Boolean functions featuring similar or better combinations of nonlinearity, correlation immunity and propagation criterion with respect to the ones obtained by other optimization methods

An analysis of traumas in medieval samples from Kliškovac and Crkvari

U radu su analizirane osobe s dva srednjovjekovna nalazišta iz kontinentalne Hrvatske: Crkvara i Kliškovca. Na spomenutim nalazištima do danas je otkopana 121 osoba (47 djece, 27 žena i 47 muškaraca), od kojih su za analizu učestalosti i distribucije trauma uzete odrasle osobe (n=74). Prosječna starost muškaraca u analiziranom uzorku je 37,4 godina, a žena 36,5 godina. Ukupno je analizirano 573 dugih kostiju. Ukupna učestalost trauma na postkranijalnim kostima iznosi 2,8% (16/573). Antemortalne traume su uočene kod 14 osoba (8 žena i 6 muškaraca), a perimortalne kod šest osoba (četiri žene i dva muškarca). Sve perimortalne traume nanesene su oštrobridnim oružjem (najvjerojatnije mačem ili bojnim nožem). Učestalost trauma glave iznosi 16,7%. Kao i kod postkranijalnih trauma prisutan je velik broj perimortalnih ozljeda. Usporedba s više osteoloških uzoraka iz Hrvatske i svijeta pokazuje da je uzorak iz Crkvara i Kliškovca specifičan po visokim učestalostima kranijalnih trauma i velikom broju perimortalnih fraktura. Zajedno, ovi podaci sugeriraju visoki rizik od međuljudskog nasilja na analiziranim nalazištima. Činjenica da su četiri od šest osoba s perimortalnim posjekotinama bile žene, sugerira da su uočene traume prije bile rezultat nasilja kojega su provodili lako naoružani i brzi pljačkaški odredi, čiji je cilj bio teroriziranje i pljačkanje civilnog stanovništva, negoli nasilja koje je bilo rezultat sukoba dviju vojski. Buduća multidisciplinarna osteološka, arheološka i povijesna istraživanja potrebna su da se potvrde rezultati dobiveni na ovom uzorku i pokušaju identificirati specifične epizode namjernog nasilja koje su prouzročile evidentirane traume.The paper presents an analysis of human remains from two medieval sites in continental Croatia: Crkvari and Kliškovac. To date, the remains of 121 persons (47 children, 27 women and 47 men) have been excavated from the two sites, and the remains of adult individuals (n=74) have been studied to determine the frequency and distribution of traumas. The average age of males in the analysed sample was 37.4 years, while the average age of females was 36.5 years. A total of 573 long bones were analysed. The overall frequency of trauma on postcranial bones was 2.8% (16/573). In 14 persons (8 females and 6 males), signs of antemortem trauma were observed, while in 6 individuals (4 women and 2 men) perimortem trauma were observed. All perimortem traumas were caused by sharp bladed weapon (probably a sword or battle knife). The overall frequency of cranial trauma was 16.7%. Similar to the postcranial traumas, among these traumas there were several perimortem injuries. A comparison with a number of osteological series from Croatia and other parts of the world shows that the Crkvari and Kliškovac sample is specific because of the high frequency of cranial traumas and the large number of perimortem fractures. Considered together, these results indicate that there was a high risk of interhuman violence at the analysed sites. The fact that four out of six persons with perimortem cuts were women suggests that the observed injuries may have been the results of violence committed by swiftly-moving armed marauding gangs, set on terrorising and looting the civilian population, rather than the results of armed clashes between two military groups. Further multidisciplinary research incorporating osteological, archaeological and historical analysis is necessary to confirm the results obtained from this sample, and to attempt to identify specific episodes of intentional violence that resulted in the observed traumas