Patent ID: 7434070
Filing Date: 2008-10-07
Classification: G06F,G06Q,G07F

Abstract:
1. A method of accessing data processing means associated with a secret code and accessible by means of a host terminal applying a presented code to said data processing means, said method comprising the steps wherein, each time the processing means are used, a constant number of predetermined operations are performed, said operations including comparisons block-by-block of the presented code and of the secret code so long as the compared blocks are identical, and comparisons block-by-block of a fraction of the presented code and of a fraction of a determined number whenever compared blocks of the presented code and of the secret code are different, until all of the blocks of the presented code have been compared, so as to obtain a succession of executed operations that is constant whether the presented code is correct, partially erroneous, or totally erroneous.