摘要 |
An authentication method of a prover device (1) by a verifier device (2) by means of cryptographic coupons is provided for, wherein a coupon comprises, on one hand, a pseudo-random number r i , where i is an index for labeling the coupon, and, on the other hand, a reduced-coupon x i such that x i = f ( r i ), where f is a predetermined one-way function, comprising at least the following steps: the verifier device (2) sends a challenge consisting of a random value c to the prover device (1); the prover device (1) sends to the verifier device (2) a response y calculated by using a pseudo-random number r i , said challenge c , and a secret key s belonging to the prover device (1); and the verifier device checks the validity of said response y based on the challenge c , the reduced-coupon x i corresponding to said pseudo-random number r i , and a public key V corresponding to said secret key s . According to the invention, the verifier device (2) receives said reduced-coupon x i from a source (3) external to the prover device (1). Application to Digital Rights Management. |