An identity management system incorporates privacy management processes that enable the user to exercise privacy controls over the disclosure of user identity information within the context of an authentication process. Embodiments of the invention advantageously wind a word line around a magnetic memory cell to increase the magnetic field induced by the word line. Crystalline nuclei are created in the solution by controlling a partial pressure of a gas made up of the same components as those of the solvent in the vicinity of the droplets immediately after being arranged to, e. For this purpose, and also for determining the number of tracks crossed by the scanning beams, it is proposed to determine the number of zero crossings and also the phase difference between at least two error signals derived from the reflected scanning beams.