Patent ID: 7509292
Filing Date: 2009-03-24
Classification: B41J,G06F,G06Q,H04N

Abstract:
1. A method for validating the authenticity of an untrusted chip, the method includes the steps of: a) generating a random number and applying an asymmetric encrypt function to the random number using a public key to produce a first variable; b) passing the first variable to the untrusted chip; c) receiving a third variable together with a data message read from the untrusted chip, the third variable having been generated, in the untrusted chip, by a process including: f) decrypting the third variable with the asymmetric decrypt function and using the public key to generate a fourth variable and comparing the fourth variable with the generated random number and the received data message; g) in the event of a match, considering the untrusted chip and the data message to be valid;