Filter by content type

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

Remove all filters

733 results

    • Seminar

    • Cryptography

    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[…]
    • Seminar

    • Cryptography

    Lossy trapdoor primitives, zero-knowledge proofs and applications

    • October 04, 2019

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

    Speaker : Chen Qian - soutenance de thèse salle Métivier à l'IRISA, 14h

    In this thesis, we study two differentprimitives. Lossy trapdoor functions and zero-knwoledge proof systems.The lossy trapdoor functions (LTFs) arefunction families in which injective functionsand lossy ones are computationally indistin-guishable. Since their introduction, they havebeen found useful in constructing various cryp-tographic primitives. We give in this thesisefficient constructions of[…]
    • Seminar

    • Cryptography

    Improved Cryptanalysis of Rank Metric Schemes Based on Gabidulin Codes.

    • February 03, 2017

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

    Speaker : Hervé Talé Kalachi - Université de Rouen et Université de Yaoundé, Cameroun

    In this presentation, we prove that any variant of the GPT cryptosystem which uses a right column scrambler over the extension field as advocated by the works of Gabidulin et al. with the goal to resist to Overbeck’s structural attack are actually still vulnerable to that attack. We show that by applying the Frobenius operator appropriately on the public key, it is possible to build a Gabidulin[…]
    • Seminar

    • Cryptography

    Investigating LWE without Modular Reduction

    • October 27, 2017

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

    Speaker : Jonathan Bootle - UCL

    The LWE problem is ubiquitous in lattice cryptography. In order to try and design more efficient cryptosystems, an increasing number of LWE variants are being considered. In this talk, we consider a variant of LWE over the integers i.e. without modular reduction. We explain why the problem is easy to solve with a large number of samples, and show how this leads to a side-channel attack on the[…]
    • Seminar

    • Cryptography

    A Modular Security Analysis of EAP and IEEE 802.11

    • April 07, 2017

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

    Speaker : Haakon Jacobsen - TBD

    The Extensible Authentication Protocol (EAP) is a widely used three-party authentication framework that allows a client to connect to a wireless access point it does not share a secret with, using a mutually trusted server. EAP is often found in enterprise networks or large organizations to provide central key-management and user authentication; one prime example being the eduroam network.<br/> In[…]
    • Seminar

    • Cryptography

    Short McEliece key from algebraic geometry codes with automorphism

    • January 26, 2018

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

    Speaker : elise barelli - INRIA Saclay

    In 1978, McEliece introduced a public key encryption scheme based on linear codes and suggested to use classical Goppa codes, ie: subfield subcodes of algebraic geometric (AG) codes built on a curve of genus 0. This proposition remains secure and in order to have a generalization of classical Goppa codes, in 1996, H. Janwa and O. Moreno suggested to use subfield subcode of AG codes, which we call[…]