Etude des systèmes d'horodatage

This paper is a survey of the state of the art in electronic time-stamping. Time- stamping of electronic documents is a cryptographic technique which is used to prove that a document was created at a certain date and that it has not been modified since then. The development of secure time-stamping systems represents a significant challenge for our societies which are increasingly using new communication and information technologies. In this paper, we classify and study the various existing time-stamping schemes and present some implemented systems. We particularly focus on the constraints which are to be satisfied when developing a secure time-stamping system. MOTS-CLES : Horodatage, confiance, systeme centralise, systeme distribue, schema de liaison, arbre binaire, accumulateurs.