International audience

In this paper, we propose a new method for optimizing the deployment of security solutions within an IoT network. Our approach uses dominating sets and centrality metrics to propose an IoT security framework where security functions are optimally deployed among devices. An example of such a solution is presented based on EndToEnd like encryption. The results reveal overall increased security within the network with minimal impact on the traffic.

Fingerprint analysis is a very important issue in biometry. The minutiae representation of a fingerprint is the most used modality to identify people or authorize access when using a biometric system. In this paper, we propose some features based on triangle parameters from the Delaunay triangulation of minutiae. We show the benefit of these features to recognize the type of a fingerprint without any access to the associated fingerprint image.

In this paper, we deal with the proof of ownership or legitimate usage of a digital content, such as an image, in order to tackle the illegitimate copy. The proposed scheme based on the combination of the watermarking and cancelable biometrics does not require a trusted third party, all the exchanges are between the provider and the customer. The use of cancelable biometrics allows us to provide a privacy compliant proof of identity. We illustrate the robustness of this method against intentional and unintentional attacks of the watermarked content.

Image quality is an important factor for automated fingerprint identification systems (AFIS) because the matching performance could be significantly affected by poor quality samples. Most of the existing studies mainly focus on calculating a quality index via either a single feature or a combination of multiple features, and some others achieve this purpose with learning approaches which may depend on a prior-knowledge of matching performance. In this paper, a general framework for estimating fingerprint image quality is proposed by fusing features in segmentation phase. The quality index is indicated by a ratio of the pixel number of the integrated foreground area to the size (pixel number) of the fingerprint image. The potential advantage of this framework is that it could be improved by integrating other segmentation approaches or quality features rather than fusing them in a more complicated manner. The experiment is performed with several fingerprint datasets created via different sensors. Experimental results obtained from a dual evaluation approach demonstrate the validity of the proposed method in improving the overall performance.

Nowadays, when someone wants to make a payment with a smartcard, the user has to enter a pin code to be identified. Only biometrics is able to authenticate a user; yet biometric information is sensitive. To ensure the security and privacy of biometric data, OCC (On-Card-Comparison) has been proposed. This approach consists in storing biometric data in a secure zone on a smartcard and computing the verification decision in a Secure Element (SE). The purpose of this paper is to propose an evaluation platform for testing biometric systems such as the analysis of performance and security on biometric OCC. Based on two examples, we illustrate its different uses in an operationnal context. The first example focus on the ”Quality module” which allows to choose the enrollment by considering the fingerprint quality with one proposed metric. The second one addresses the minutiae reduction of the fingerprint template when the number of minutiae is higher than expected by the OCC.

This article proposes a new quality assessment method of fingerprint, represented by only a set of minutiae points. The proposed quality metric is modeled with the convex-hull and Delaunay triangulation of the minutiae points. The validity of this quality metric is verified on several Fingerprint Verification Competition (FVC) databases by referring to an image-based metric from the state of the art (considered as the reference). The experiments of the utility-based evaluation approach demonstrate that the proposed quality metric is able to generate a desired result. We reveal the possibility of assessing fingerprint quality when only the minutiae template is available.

Biometric sample quality assessment approaches are generally designed in terms of utility property due to the potential difference between human perception of quality and the biometric quality requirements for a recognition system. This study proposes a utility based quality assessment method of fingerprints by considering several complementary aspects: 1) Image quality assessment without any reference which is consistent with human conception of inspecting quality, 2) Textural features related to the fingerprint image and 3) minutiae features which correspond to the most used information for matching. The proposed quality metric is obtained by a linear combination of these features and is validated with a reference metric using different approaches. Experiments performed on several trial databases show the benefit of the proposed fingerprint quality metric.

Boolean functions are very important cryptographic primitives in stream or block ciphers. In order to be useful for cryptographic applications, these functions should satisfy some properties like high algebraic degree, high non linearity or being correlation immune. Since for most of the cryptographic criteria presented in the literature there is no complete characterization of the set of functions that optimally satisfy any of them, the possibility of finding an enumerative encoding of any such class of functions is extremely hard. In a recent paper Le Bars and Viola have presented an innovative recursive decomposition of the first order correlation immune Boolean functions. It is not a trivial task, however, to derive from this characterization an enumerative encoding. This paper presents an enumerative encoding for first order correlation immune functions. It provides the first enumerative encoding of a class of Boolean functions with cryptographic applications. The encoding naturally leads to efficient random generation algorithms. For example, we may construct, with uniform probability, any 1-resilient function (balanced first order correlation immune function) with 8 variables in less than 30 seconds, from a universe of around 1068functions

In 2002, in two independent papers, Bellare, Kohno, and Namprempre and Joux, Martinet, and Valette introduced the notion of blockwise security for modes of operations. This notion stems from common practice, since in many applications, modes of operation for block ciphers do not process messages as atomic entities but in a incremental manner, block after block. Soon afterward, several papers showed that many modes of operation are already blockwise secure and that others can be made secure by simple modifications. In this paper, we revisit these results, by comparing possible attacks on modes of operation after the birthday bound is reached. Amusingly, in spite having essentially identical security proofs up to this bound, modes of operation in the blockwise model behave very differently than their counterparts in the regular model, once the birthday paradox bound is crossed.

Boolean functions are very important cryptographic primitives in stream or block ciphers. In this context, these functions need to satisfy good properties like high algebraic degree, nonlinearity and correlation immunity. We present here an original and efficient method to enumerate all the correlation-immune functions of a fixed Hamming weight, in particular the class of 1-resilient functions. The key idea consists in defining equivalent classes to split boolean functions along their distance from correlation-immune boolean functions. These classes, called first-order correlation classes, are built using a recursive decomposition of smaller classes. We derive from this method several algorithms to enumerate their elements and to count their cardinality. We first show that the exact number of 1-resilient boolean functions with 7 variables is 23478015754788854439497622689296 and we obtain a tight estimation of their number with 8 variables, between 4 1067and 5.6 1068. We then present a general lower bound for the number of 1-resilient boolean functions and improve Schneider's upper bound. We also propose a general lower bound for the number of k-resilient functions. Most of the bounds presented in this paper, substantially improve the best known bounds in the literature. We finally establish that the probability of a Boolean function being 1-resilient is asymptotically between (npi)n/2/2n2-3/2n-1en-1/2.

The digraph property KERNEL is a very simple and wellknown property studied in various areas. We previously defined a variant of this property as a counterexample of 0-1 law for the monadic existential second order logic with at most two first-order variables, over structures with 16 binary relations. Goranko and Kapron have defined two variants in frames which expresses frame satisfiability of propositional modal logic, also expressible in a small fragment of the logic above over structures with only one relation. We propose another variant of KERNEL which provides a counterexample of the 0-1 law for frame satisfiability of propositional modal logic. This refutes a result by Halpern and Kapron which establishes that the 0-1 law holds for this logic. It also strongly refines our previous counterexample.

We prove that there is a Monadic /spl Sigma//sub 1//sup 1/ (Minimal Scott without equality) sentence without an asymptotic probability. Our result entails that the 0-1 law fails for the logics /spl Sigma//sub 1//sup 1/(FO/sup 2/) and /spl Sigma//sub 1//sup 1/ (Minimal Godel without equality). Therefore we achieve the classification of first-order prefix classes with or without equality. According to the existence of the 0-1 law for the corresponding /spl Sigma//sub 1//sup 1/ fragment. In addition, our counterexample can be viewed as a single explanation of the failure of the 0-1 law of all the fragments of existential second-order logic for which the failure is already known.