511 results

  • On Rejection Sampling in Lyubashevsky's Signature Scheme

    • May 06, 2022

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Julien Devevey - ENS de Lyon

    Lyubashevsky’s signatures are based on the Fiat-Shamir with aborts paradigm, whose central ingredient is the use of rejection sampling to transform (secret-key-dependent) signature samples into samples from a secret-key-independent distribution. The choice of these two underly- ing distributions is part of the rejection sampling strategy, and various instantiations have been considered up to this[…]
  • Traceable Constant-Size Multi-Authority Credentials

    • April 29, 2022

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Chloé Hébant - ENS

    Many attribute-based anonymous credential (ABC) schemes have been proposed allowing a user to prove the possession of some attributes, anonymously. They became more and more practical with, for the most recent papers, a constant-size credential to show a subset of attributes issued by a unique credential issuer. However, proving possession of attributes coming from K different credential issuers[…]
  • Constant time implementation of rank based cryptography

    • April 01, 2022

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Nicolas Aragon - IRISA

    Since the start of the NIST standardization project for post-quantum cryptography in 2017, rank metric based cryptography is becoming more popular as an alternative to code-based cryptography in the Hamming metric.<br/> While rank based cryptography has always been competitive in terms of keys and ciphertexts sizes, the lack of maturity in the implementations of these cryptosystems made them[…]
  • Public Key Encryption with Flexible Pattern Matching

    • March 25, 2022 (00:00 - 23:59)

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Elie Bouscatié - Orange

    Many interesting applications of pattern matching (e.g. deep-packet inspection or medical data analysis) target very sensitive data. In particular, spotting illegal behaviour in internet traffic conflicts with legitimate privacy requirements, which usually forces users to blindly trust an entity that fully decrypts their traffic in the name of security. The compromise between traffic analysis and[…]
  • Soutenance de thèse: Problème du logarithme discret sur des courbes elliptiques

    • January 28, 2022

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : 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[…]
  • TBA

    • January 14, 2022

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Louiza Khati - Anssi

    TBA lien: https://univ-rennes1-fr.zoom.us/j/97066341266?pwd=RUthOFV5cm1uT0ZCQVh6QUcrb1drQT09