Vorrichtung und Verfahren zur effizienten einseitigen Authentifizierung

The device (100) has a random number generator (110) for producing a random number (r), and an elliptic curve processor (120) for computing a x-coordinate (xR) of a curve dot of a fixed elliptic curve based on a scalar multiplication of the random number with a base point (P) of the fixed elliptic curve. The processor provides the x-coordinate and an authentication variable (V) as authentication data for single authentication. The processor varies a control variable in a predetermined manner before computing a new authentication variable for the repeated single authentication.; Independent claims are also included for the following: (1) a device for verifying authentication data comprising a receiver for receiving the authentication data (2) a method for providing authentication data for repeatable single authentication (3) a method for verifying authentication data for repeatable single authentication (4) a computer program comprising a program code for executing a method for verifying authentication data for repeatable single authentication.