Description
Depuis les travaux de Hafner-MacCurley et Buchmann, le calcul du groupe de classes et d'unités d'un corps de nombres est connu comme étant possible en temps sous-exponentiel sous GRH pour les classes de corps de degré fixé.<br/> Dans cet exposé, nous montrerons qu'il est possible d'étendre ces résultats aux corps de nombres de degré tendant vers l'infini. Nous envisagerons des applications à des domaines liés à la cryptographie. En particulier, le calcul de relations entre idéaux du groupe de classes polarisé qui intervient dans le cadre du calcul d'isogénies entre variétés abéliennes, et le calcul du générateur d'un idéal principal qui permet la cryptanalyse de certain systèmes de chiffrement homomorphe.
Next sessions
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SoK: Security of the Ascon Modes
Speaker : Charlotte Lefevre - Radboud University
The Ascon authenticated encryption scheme and hash function of Dobraunig et al (Journal of Cryptology 2021) were recently selected as winner of the NIST lightweight cryptography competition. The mode underlying Ascon authenticated encryption (Ascon-AE) resembles ideas of SpongeWrap, but not quite, and various works have investigated the generic security of Ascon-AE, all covering different attack[…] -
Comprehensive Modelling of Power Noise via Gaussian Processes with Applications to True Random Number Generators
Speaker : Maciej Skorski - Laboratoire Hubert Curien
The talk examines power noise modelling through Gaussian Processes for secure True Random Number Generators. While revisiting one-sided fractional Brownian motion, we obtain novel contributions by quantifying posterior uncertainty in exact analytical form, establishing quasi-stationary properties, and developing rigorous time-frequency analysis. These results are applied to model oscillator[…]-
Cryptography
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TRNG
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CryptoVerif: a computationally-sound security protocol verifier
Speaker : Bruno Blanchet - Inria
CryptoVerif is a security protocol verifier sound in the computational model of cryptography. It produces proofs by sequences of games, like those done manually by cryptographers. It has an automatic proof strategy and can also be guided by the user. It provides a generic method for specifying security assumptions on many cryptographic primitives, and can prove secrecy, authentication, and[…]-
Cryptography
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