Implementing Lightweight Block Ciphers on x86 Architectures

Abstract. Lightweight block ciphers are designed so as to fit into very constrained environments, but usually not really with software performance in mind. For classical lightweight applications where many constrained devices communicate with a server, it is also crucial that the cipher has good software performance on the server side. Recent work has shown that bitslice implementations applied to Piccolo and PRESENT led to very good software speeds, thus making lightweight ciphers interesting for cloud applications. However, we remark that bitslice implementations might not be interesting for some situations, where the amount of data to be enciphered at a time is usually small, and very little work has been done on non-bitslice implementations. In this article, we explore general software implementations of lightweight ciphers on x86 architectures, with a special focus on LED, Piccolo and PRESENT. First, we analyze table-based implementations, and we provide a theoretical model to predict the behavior of various possible trade-offs depending on the processor cache latency profile. We obtain the fastest table-based implementations for our lightweight ciphers, which is of interest for legacy processors. Secondly, we apply to our portfolio of primitives the vperm implementation trick for 4-bit Sboxes, which gives good performance, extra side-channels protection, and is quite fit for many lightweight primitives. Finally, we investigate bitslice implementations, analyzing various costs which are usually neglected (bitsliced form (un)packing, key schedule, etc.), but that must be taken in account for many lightweight applications. We finally discuss which type of implementation seems to be the best suited depending on the applications profile

Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites

The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples.Peer reviewe

The Compact Linear Collider (CLIC) - 2018 Summary Report

The Compact Linear Collider (CLIC) is a TeV-scale high-luminosity linear $e^+e^-$ collider under development at CERN. Following the CLIC conceptual design published in 2012, this report provides an overview of the CLIC project, its current status, and future developments. It presents the CLIC physics potential and reports on design, technology, and implementation aspects of the accelerator and the detector. CLIC is foreseen to be built and operated in stages, at centre-of-mass energies of 380 GeV, 1.5 TeV and 3 TeV, respectively. CLIC uses a two-beam acceleration scheme, in which 12 GHz accelerating structures are powered via a high-current drive beam. For the first stage, an alternative with X-band klystron powering is also considered. CLIC accelerator optimisation, technical developments and system tests have resulted in an increased energy efficiency (power around 170 MW) for the 380 GeV stage, together with a reduced cost estimate at the level of 6 billion CHF. The detector concept has been refined using improved software tools. Significant progress has been made on detector technology developments for the tracking and calorimetry systems. A wide range of CLIC physics studies has been conducted, both through full detector simulations and parametric studies, together providing a broad overview of the CLIC physics potential. Each of the three energy stages adds cornerstones of the full CLIC physics programme, such as Higgs width and couplings, top-quark properties, Higgs self-coupling, direct searches, and many precision electroweak measurements. The interpretation of the combined results gives crucial and accurate insight into new physics, largely complementary to LHC and HL-LHC. The construction of the first CLIC energy stage could start by 2026. First beams would be available by 2035, marking the beginning of a broad CLIC physics programme spanning 25-30 years

Efficient Vector Implementations of AES-Based Designs: A Case Study and New Implemenations for Grøstl,Efficient Vector Implementations of AES-Based Designs : a Case Study and New Implemenations [sic] for Grøstl

Contains fulltext : 116968.pdf (preprint version ) (Closed access

Mutation-Based Test Case Generation for Simulink Models

The Matlab/Simulink language has become the standard formalism for modeling and implementing control software in areas like avionics, automotive, railway, and process automation. Such software is often safety critical, and bugs have potentially disastrous consequences for people and material involved. We define a verification methodology to assess the correctness of Simulink programs by means of automated test-case generation. In the style of fault- and mutation-based testing, the coverage of a Simulink program by a test suite is defined in terms of the detection of injected faults. Using bounded model checking techniques, we are able to effectively and automatically compute test suites for given fault models. Several optimisations are discussed to make the approach practical for realistic Simulink programs and fault models, and to obtain accurate coverage measures

Mechanisms and mediators of nasal symptoms in non-allergic rhinitis

Non-allergic rhinitis may be a contributing factor in up to 60% of rhinitis patients and a sole contributor in a quarter. It is a highly heterogeneous condition with poorly understood pathophysiological mechanisms. Compelling evidence is emerging of a localized nasal mucosal allergic response in some non-allergic rhinitic subjects in the absence of systemic atopy. While the inflammatory disease pathway in non-allergic rhinitis may share some of the features of its allergic counterpart, overall the mechanisms remain unclear, and there are likely to be differences. In particular, symptoms of nasal congestion and rhinorrhoea tend to be more prominent and persistent in non-allergic rhinitic patients compared with allergic rhinitis. Our aim is to review the literature relating to mechanisms and mediators of nasal symptoms in non-allergic rhinitis. Better understanding of the underlying pathophysiological basis should enable the development of more accurate testing, and better targeted therapeutic options in the future