Patent ID: 8484750

Claim:
A method of verifying that a current system with which a second group of parameters is associated is authorized to execute software allowing implementation of a computer program and/or access to data, the computer program and/or the data having been previously coupled to a reference system with which a first group of parameters is associated, by protecting a value V 0 associated with the reference system and necessary for the execution of said software, in alliance with at least one parameter of the first group of parameters the method comprising: protecting the value V 0 by constructing and storing a table; wherein the table comprises: for each element t of a set of subsets of said first group of parameters satisfying a predetermined criterion, a data pair (g_t(X); h_t(V 0 )), where g_t denotes a function dependent on t, h_t denotes an invertible, bijective function dependent on t, and X denotes an element in the defining set of g_t retrieving by a processing device the value V 0 on the basis of at least one parameter of said second group of parameters according to the following steps: calculating g_t′(X), for at least certain elements t′ of a set of subsets of said second group of parameters; comparing g_t′(X) with certain at least of the data g_t(X) stored in the table; and in the event of agreement between g_t′(X) and a data item g_t(X) stored in the table: retrieving the value h_t(V 0 ) stored in the table and belonging to the data pair comprising said data item g_t(X); and applying the inverse function of h_t to h_t(V 0 ) to retrieve the value V 0 associated with the reference system.