Séminaire Algorithmique : « Enumeration Classes Defined by Circuits », Arnaud Durand (IMJ, Univ. Paris-Diderot)
Sciences 3- S3 351Enumerating is the task of generating all solutions associated with an instance of a computational problem. We refine the complexity landscape for enumeration problems by introducing very low classes defined by using Boolean circuits as enumerators. We locate well-known enumeration problems, e.g., from graph theory, Gray code enumeration, and propositional satisfiability in our classes. In … Continue reading Séminaire Algorithmique : « Enumeration Classes Defined by Circuits », Arnaud Durand (IMJ, Univ. Paris-Diderot)
Pascal Marchand – A la recherche des signes complotistes en ligne: exploration et expérimentation par la textométrie.
Sciences 3- S3 351On se situera à l’intersection des sciences de données et des sciences cognitives pour qualifier formellement les rhétoriques et représentations mobilisées dans les commentaires en ligne sur la vaccination. Le corpus (135 620 textes, 5 481 450 occurrences et 53 835 formes lexicales) fait d'abord l’objet d’une classification hiérarchique descendante (CDH). Pour l’interpréter, on mobilise … Continue reading Pascal Marchand – A la recherche des signes complotistes en ligne: exploration et expérimentation par la textométrie.
Séminaire algorithmique : Vincent Jugé (LIGM, Univ. G. Eiffel, Paris Est), « Write-efficient updates for AVL trees »
Sciences 3- S3 351Balanced binary search trees are a common data structure for implementing ordered sets, with three kinds of queries: checking whether a given value belongs to the set, inserting a value, and deleting a value; the two latter queries require updating the data structure. Some implementations, like red-black trees or weak AVL trees, allow efficient update … Continue reading Séminaire algorithmique : Vincent Jugé (LIGM, Univ. G. Eiffel, Paris Est), « Write-efficient updates for AVL trees »
Laura Luzzi – Finite blocklength secrecy analysis of polar and Reed-Muller codes in binary erasure wiretap channels
Sciences 3- S3 351Physical layer security aims to exploit the randomness of noisy channels in order to enhance security through coding and signal processing techniques. Unlike cryptography, it does not place any limitations on the adversary's computational power, but relies on an asymmetry in the channel quality between the legitimate users and the adversary. In this talk, we … Continue reading Laura Luzzi – Finite blocklength secrecy analysis of polar and Reed-Muller codes in binary erasure wiretap channels
Kévin Carrier – Combinatorial Attacks On The Decoding Problem
Sciences 3- S3 351The decoding problem is fundamental in post-quantum cryptography. It can be broadly described as essentially solving a linear system with a non-linear constraint on the solution. Phrased this way, the problem applies to both code-based and lattice-based cryptography. For example, the linear system may be defined over FF_q, with the non-linear constraint being a condition … Continue reading Kévin Carrier – Combinatorial Attacks On The Decoding Problem
Séminaire Algorithmique : Josselin Guéneron (GREYC) « Repeated Stochastic Coalition Formation: representations and algorithmic approaches »
Sciences 3- S3 351Coalition formation is a cooperative game theory framework in which a set of agents, required to perform implicit or explicit tasks, must be divided into subgroups (called coalitions), according to collective criteria and a utility function describing the utility of each coalition. This is equivalent to a problem of partitioning the set of agents. The … Continue reading Séminaire Algorithmique : Josselin Guéneron (GREYC) « Repeated Stochastic Coalition Formation: representations and algorithmic approaches »
Séminaire Algorithmique : Nicolas Bitar (LAMFA, Univ. Picardie), « Subshifts of finite type and quasi-isometries beyond groups »
Sciences 3- S3 351In 1964, R. Berger proved the existence of strongly aperiodic subshifts of finite type (SFT) on $\mathbb{Z}^2$, and used them to prove the undecidability of the Domino Problem. With the goal of understanding what aspects of $\mathbb{Z}^2$ account for this result, there has been an effort in recent years to characterize the groups with undecidable … Continue reading Séminaire Algorithmique : Nicolas Bitar (LAMFA, Univ. Picardie), « Subshifts of finite type and quasi-isometries beyond groups »
Tristan Benoît – Approche multimodale pour la génération de noms de fonctions à partir du code binaire
Sciences 3- S3 351La compréhension du code binaire est cruciale en rétro-ingénierie. Usuellement, des bases de fonctions servent à identifier dans un binaire les fonctions proches de références connues. Cependant, souvent les projections sous-jacentes traitent chaque code source séparément. En revanche, les modèles de langage récents permettent de projeter le code binaire et sa description textuelle dans un … Continue reading Tristan Benoît – Approche multimodale pour la génération de noms de fonctions à partir du code binaire
Mengce Zheng – Lattice-based solving strategy using Coppersmith’s techniques and its applications
Sciences 3- S3 351Lattice-based cryptanalysis using Coppersmith's techniques has emerged as a powerful approach to compromising the security of several cryptographic algorithms under specific conditions. This talk will provide an exploration of the lattice-based solving strategy, which leverages lattice basis reduction to find small roots of polynomial equations modulo an integer. This method is then used for examining … Continue reading Mengce Zheng – Lattice-based solving strategy using Coppersmith’s techniques and its applications
Victor Mollimard – Partial Sums Meet FFT: Improved Attack on 6-roued AES
Sciences 3- S3 351The partial sums cryptanalytic technique was introduced in 2000 by Ferguson et al., who used it to break 6-round AES with time complexity of $2^{52}$ S-box computations -- a record that has not been beaten ever since. In 2014, Todo and Aoki showed that for 6-round AES, partial sums can be replaced by a technique … Continue reading Victor Mollimard – Partial Sums Meet FFT: Improved Attack on 6-roued AES
Séminaire Algorithmique : « Enumeration of some families of chordal graphs », Jordi Castellvi (Univ. Barcelone, Espagne)
Sciences 3- S3 351A graph is chordal if it has no induced cycle of length greater than 3. Alternatively, Dirac proved that a graph is chordal if and only if every minimal separator is a clique. From this characterization it is not hard to prove that a k-connected chordal graph can be uniquely decomposed into (k+1)-connected components by … Continue reading Séminaire Algorithmique : « Enumeration of some families of chordal graphs », Jordi Castellvi (Univ. Barcelone, Espagne)
Abdelhamid Garah – Gestion autonome des services de sécurité dans l’Internet des objets
En distancielL’Internet des objets (IoT : Internet of Things) et ses applications sont devenus indispensables dans notre vie quotidienne. Cependant, la croissance rapide des systèmes IoT a engendré d’importants défis en matière de sécurité. De nombreux dispositifs IoT sont naturellement vulnérables en raison des contraintes de ressources telles que la capacité de traitement et l’autonomie de … Continue reading Abdelhamid Garah – Gestion autonome des services de sécurité dans l’Internet des objets