599 results

  • 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[…]
  • Towards Non-Interactive Zero-Knowledge from CDH and LWE

    • January 18, 2019

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

    Speaker : Geoffroy Couteau - Karlsruher Institut für Technologie (KIT)

    We provide a generic construction of non-interactive zero-knowledge (NIZK) schemes. Our construction is a refinement of Dwork and Naor’s (FOCS 2000) implementation of the hidden bits model using verifiable pseudorandom generators (VPRGs). Our refinement simplifies their construction and relaxes the necessary assumptions considerably. As a result of this conceptual improvement, we obtain[…]
  • Privacy in The 5G-AKA Authentication Protocol

    • January 18, 2019

    • Inria Center of the University of Rennes - -Petri/Turing room

    Speaker : Adrien Koutsos (LSV)

    The 5G mobile communications standards are being finalized, and drafts are now available. This standard describes the 5G-AKA authentication and key exchange protocol. The previous version of AKA (3G and 4G) are well-known for their lack of privacy against an active adversary (e.g. a user can be massively tracked using IMSI-catcher). This new version of AKA tries to offer more privacy, notably[…]
  • Wave: A New Code-Based Signature Scheme

    • January 11, 2019

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

    Speaker : Thomas Debris-alazard - inria

    It is a long standing open problem to build an efficient and secure digital signature scheme based on the hardness of decoding a linear code which could compete with widespread schemes like DSA or RSA. The latter signature schemes are broken by a quantum computer with Shor’s algorithm. Code-based schemes could provide a valid quantum resistant replacement. We present here Wave the first « hash[…]
  • Some new results on cube attacks against Trivium

    • December 14, 2018

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

    Speaker : Tian Tian - Université de Zhengzhou

    Trivium is a bit oriented synchronous stream cipher designed by Cannière and Preneel. It is one of the eSTREAM hardware-oriented finalists and an International Standard under ISO/IEC 29192-3:2012. Cube attacks are an important type of key recovery attack against Trivium. First, I will give a survey on cube attacks against Trivium. Second, I will present our recent results including an algebraic[…]
  • Une approche pour l’accélération matérielle pour le chiffrement homomorphe

    • December 14, 2018

    • CEA List

    Speaker : Joël Cathebras

    Le chiffrement homomorphe est un outil cryptographique permettant la manipulation de données en aveugle. Son utilisation généralisée permettrait de proposer des solutions de calcul déporté impliquant des données confidentielles, par exemple des données génomiques pour la médecine personnalisée. Cependant, le chiffrement homomorphe doit faire face à de grandes complexités mémoires et calculatoires.[…]