Séminaire de Cryptographie

Accueil     Présentation     Archives

Julien Bringer

Extended Private Information Retrieval Protocols: definitions,applications & new extensions

Cet exposé est basé sur des travaux communs avec Hervé Chabanne, David Pointcheval, Qiang Tang menés dans le cadre du projet ANR RNRT BACH (Biometric Authentication with Cryptographic Handling). Extended Private Information Retrieval (EPIR) is a generalization of the notion of Private Information Retrieval (PIR). The principle is to enable a user to privately evaluate a fixed and public function with two inputs, a chosen block from a database and an additional string. In this talk, we will present this notion and describe 2 constructions with applications to biometric authentication. We will then explain an extension of this notion in order to add more flexibility during the system life. As an example, we will introduce a general protocol enabling polynomial evaluations. As to practical concern, we will also discuss how amortizing database computations when dealing with several requests.