Cryptographic method for anonymous authentication and separate identification of a user

Abstract

The invention relates to cryptographic method for the anonymous authentication and the identification of a user entity (Ui) respectively by a checking entity (D) and an identifying entity (O). According to this method, the checking entity (D) receives (130) from the user entity (U1) at least one first signature (σ) and a first message (m), and checks (140) the first signature (σ) using the first message (m) in order to authenticate the user (U), and the identifying entity (O) receives (150) from the checking entity (D) a second signature (σ′) connected to the first signature (σ) and identifies (160) the user using the second signature and a secret key particular thereto. The invention also relates to a cryptographic system for implementing said method.

Dependencies are inferred from the claim text.