Sommaire

  • Cet exposé a été présenté le 14 mars 2003.

Description

  • Orateur

    Eliane Jeaulme - DCSSI

Dans cet exposé, nous présenterons les principaux modes de chiffrement et d'authentification en cryptographie à clef secrète. Nous verrons ensuite le principe des preuves de sécurité de ces modes : les hypothèses de sécurité, le mécanisme de preuve et les théorèmes énonçant la sécurité. Nous détaillerons une application de ce principe de preuve sur le mode d'authentification RMAC. Ce mode utilise des valeurs aléatoires dans la génération du code d'authentification de message et offre une sécurité au delà du paradoxe des anniversaires.

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