Abstract: The system has a unique identifier (2) stored in client's hardware (1). Via a transfer environment (3) using a higher layer protocol (4), the unique identifier (2) is coupled to a server (5), where, in an evaluation module (6), it is connected to a substitution and calculation module (7). A w polynomial system (8) stored in the persistent memory (9) of the server (5) is also connected to the substitution and calculation module (7), the output of which is a calculated key (10). At the same time, the client's hardware (1) stores a local key (11) which is via the transfer environment (3) using the higher layer protocol (4) connected to a key comparison module (12) to which the calculated key (10) is also connected. The key comparison module (12) is through its positive output (13) and negative output (14) connected via the transfer environment (3) using the higher layer protocol (4) to a response processing module (15) which is stored in the client's hardware (1).