Time keeping device and system containing code generating means at given times, where the given times are calculated by a secret algorithm.

摘要

The field of the invention is that of timekeeping systems and devices and especially that of timekeeping devices for controlled parking durations. More precisely, the present invention relates to a system and device making it possible to check the authenticity of this type of apparatus. …According to the invention, the system comprises a plurality of boxes each held by a separate user, each box comprising calculating means (31) determining at least two secret codes, passage from one secret code to the other being effected substantially at the same moment for all the boxes and the secret codes being identical for all the boxes substantially at the same moment in order to permit the controller to check the authenticity of the boxes. The moment of code changing results from a secret calculation. ……