Table of contents

  • This session has been presented February 27, 2004.

Description

  • Speaker

    Nicolas Thériault - Université de Toronto

Au cours des dernières années, les courbes hyperelliptiques se sont imposées comme une bonne alternative aux courbes elliptiques pour la cryptographie a clé publique. Il est donc important de développer une bonne évaluation de la sécurité des cryptosystèmes qui en découlent.<br/> Dans cet expose, nous présentons certains développements récents pour deux types d'attaques contre le problème du log discret pour les Jacobiennes de courbes hyperelliptiques: le calcul d'indexe et la restriction de Weil. Nous décrivons l'impact de ces algorithmes sur la sécurité des divers cryptosytèmes et dans quelles limites ces attaques peuvent être réalisées.

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