Filtrer par type de contenu
Sélectionnez un ou plusieurs filtres. Ce choix permettra de recharger la page pour afficher les résultats filtrés.
634 résultats
-
-
Séminaire
-
Cryptographie
Soutenance de thèse: Study and design of new encryption primitives based on rank metric error correcting codes
Orateur : Ba Duc Pham - Rennes
In 2005, Faure and Loidreau proposed a new rank-metric cryptosystem inspired from the Hamming metric scheme of Augot-Finiasz in 2003. In 2018, it was broken by the attack of Gaborit, Otmani and Kalachi. Recently, there are some attempts of repairing the Faure-Loidreau scheme, for example the work of Renner, Puchinger and Wachter–Zeh which is called LIGA. In this thesis, we also introduce a new[…] -
-
-
Séminaire
-
Cryptographie
Lattice-based signatures: from construction to implementation
Orateur : Pauline Bert - soutenance de thèse, amphi P de l'ISTIC, 14h
Lattice-based cryptography is one of the major line of research to build post-quantum public key primitives. In this thesis, we discuss about digital signatures constructions and their implementation. We first describe a Fiat-Shamir transformation from an identification scheme using rejection sampling to a digital signature secure in the random oracle model. Then we describe an identity-based[…] -
-
-
Séminaire
-
Cryptographie
Code-based postquantum cryptography : candidates to standardization
Orateur : Nicolas Sendrier - INRIA
At the third round of the NIST standardization process, three candidates remain with a security based on error correcting codes, all are key exchange mechanisms. We will explore them according to their security assumptions and properties. Among them, we find an historical scheme (Classic McEliece), as well as schemes using sparse and quasi-cyclic matrices (BIKE and HQC). We will examine pros and[…] -
-
-
Séminaire
-
Cryptographie
Soutenance de thèse: Problème du logarithme discret sur des courbes elliptiques
Orateur : Andy Russon - Rennes 1 et Orange
L’usage des courbes elliptiques en cryptographie s’est largement répandu pour assurer la sécurité des communications ou de transactions financières. Cela est dû notamment au fait que la sécurité repose sur la difficulté du problème du logarithme discret qui permet d’utiliser les courbes elliptiques avec des paramètres qui assurent une efficacité.<br/> Dans cette thèse, nous abordons[…] -
-
-
Séminaire
-
Cryptographie
Cryptanalysis of code-based cryptosystems using the square-code distinguisher
Orateur : Mathieu Lequesne - INRIA
Many code-based cryptosystems have been proposed recently, especially in response to the call for post-quantum cryptography standardization issued by the National Institute of Standards and Technologie. Most code-based cryptosystem rely on the same idea: an error-correcting code with some special structural properties (including good error-correction capacity) serves as the private key. This code[…] -
-
-
Séminaire
-
Cryptographie
Decoding Supercodes of Gabidulin Codes and Applications to Cryptanalysis
Orateur : Maxime Bombar - Ecole Polytechnique
Error correcting codes are well known to provide possible candidates for building quantum safe cryptographic primitives. Besides the Hamming metric which has a long-standing history, one may consider other metrics such as the rank metric. Gabidulin codes are the rank metric analogue of Reed-Solomon codes and can be efficiently decoded up to half the minimum distance. However, beyond this radius,[…] -