Filter by content type

Select one or more filters. This choice will reload the page to display the filtered results.

Remove all filters

627 results

    • Seminar

    • Cryptography

    CSIDH: an efficient post-quantum commutative group action

    • February 01, 2019

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

    Speaker : Chloé Martindale - Technical University of Eindhoven

    CSIDH, or `commutative supersingular isogeny Diffie-Hellman' is a new isogeny-based protocol of Castryck, Lange, Martindale, Panny, and Renes.<br/> The Diffie-Hellman style scheme resulting from the group action allows for public key validation at very little cost, runs reasonably fast in practice, and has public keys of only 64 bytes at a conjectured AES-128 security level, matching NIST’s post[…]
    • Seminar

    • Cryptography

    Isogeny-based cryptography from superspecial genus-2 curves

    • October 18, 2019

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

    Speaker : Wouter Castryck - KU Leuven

    I will report on some first attempts to do isogeny-based cryptography in genus 2. More precisely, we will use isogeny graphs of superspecial principally polarized abelian surfaces over GF(p^2) for constructing variants of Charles, Goren and Lauter's hash function and of Jao and De Feo's SIDH key exchange protocol, both of which use supersingular elliptic curves over GF(p^2). This will be largely[…]
    • Seminar

    • Cryptography

    Zero-Knowledge Argument for Matrix-Vector Relations and Lattice-Based Group Encryption

    • September 28, 2018

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

    Speaker : Fabrice Mouhartem - ENS Lyon

    Group encryption (GE) is the natural encryption analogue of group signatures in that it allows verifiably encrypting messages for some anonymous member of a group while providing evidence that the receiver is a properly certified group member. Should the need arise, an opening authority is capable of identifying the receiver of any ciphertext. As intro- duced by Kiayias, Tsiounis and Yung […]
    • Seminar

    • Cryptography

    New candidate PRFs and their applications

    • April 12, 2019

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

    Speaker : Alain Passelègue - Inria

    In this talk, I will present new and simple candidate PRFs introduced in a recent work. In this work, we depart from the traditional approaches for building PRFs used in provable security or in applied cryptography by exploring a new space of plausible PRF candidates. Our guiding principle is to maximize simplicity while optimizing complexity measures that are relevant to advanced cryptographic[…]
    • Seminar

    • Cryptography

    Tunnels sécurisés pour environnements contraints

    • November 18, 2019

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

    Speaker : Loic Ferreira - soutenance de thèse salle Métivier à l'IRISA, 14h30

    Avec l’extension de l’Internet des Objets et l’usage croissant de terminaux à bas coût, de nombreux protocoles de sécurité sont déployés à grande échelle. Cette thèse étudie le champ des protocoles d’échange de clé authentifié basés sur des fonctions cryptographiques symétriques. Nous montrons que les protocoles existants n’atteignent pas un niveau de sécurité correspondant à l’état de l’art en[…]
    • Seminar

    • Cryptography

    Repairing the Faure-Loidreau Public-Key Cryptosystem

    • November 23, 2018

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

    Speaker : julian renns - Teschnische Universität Munchen

    A repair of the Faure–Loidreau (FL) public-key code-based cryptosystem is proposed. The FL cryptosystem is based on the hardness of list decoding Gabidulin codes which are special rank-metric codes. We prove that the recent structural attack on the system by Gaborit et al. is equivalent to decoding an interleaved Gabidulin code. Since all known polynomial-time decoders for these codes fail for a[…]