Abstract EN:

Interactions on the Internet require trust between each involved party. Internet entities assume, at the same time, several roles, each having their own interests and motivations; leading to conflicts that must be addressed to enable security and trust. In this thesis, we use, and focus on, Keystroke Dynamics (the way a user type on its keyboard) in an attempt to solve some of these conflicts.Keystroke Dynamics is a a costless and transparent biometric modality as it does not require neither additional sensors nor additional actions from the user. Unfortunately, Keystroke Dynamics also enables users profiling (s.a. identification, gender, age), against their knowledge and consent.In order to protect users privacy, we propose to anonymize Keystroke Dynamics. Still, such information can be legitimately needed by services in order to straighten user authentication. We then propose a Personal Identity Code Respecting Privacy, enabling biometric users authentication without threatening users privacy.We also propose a Social Proof of Identity enabling to verify claimed identities while respecting user privacy, as well as ensuring users past behaviors through a system of accountability. Generation of synthetic Keystroke Dynamics is also considered to augment existent Keystroke Dynamics datasets, and, in the end, enabling sharing of Keystroke Dynamics datasets without exposing biometric information of real users.