State-of-the-art authentication does little to account for the way in which users interact. For example, knowledge-based authentication schemes such as PIN, lock patterns, or passwords were invented at times where people authenticated with very few devices and only a few times per day. At the same time, as a result of crowd services and smart devices, users today access sensitive information through 100 accounts on average and authenticate several hundred times a day. This leads to a significant overhead in authentication times and users are forced to use more passwords than they can remember.

In contrast, implicit authentication schemes hold a lot of promise as they can operate seamlessly in the background. In particular, we look at how knowledge about users' behavior can be leveraged to build authentication schemes that are both more usable and more secure. We are interested in the technical foundations of such schemes (How can we build suitable authentication models? How can we use them across applications and contexts?) and in the users' view (How can implicit mechanisms be built that preserve users' privacy? How can the acceptance of users' be increased?).

Publications

liebers2021chi.jpg Jonathan Liebers, Uwe Gruenefeld, Lukas Mecke, Alia Saad, Jonas Auda, Florian Alt, Mark Abdelaziz and Stefan Schneegass. Understanding User Identification in Virtual Reality through Behavioral Biometrics and the Effect of Body Normalization. In Proceedings of the 2021 CHI Conference on Human Factors in Computing Systems. CHI'21. Association for Computing Machinery, New York, NY, USA. [Download Bibtex]
pfeuffer2019chi.jpg Ken Pfeuffer, Matthias Geiger, Sarah Prange, Lukas Mecke, Daniel Buschek and Florian Alt. Behavioural Biometrics in VR - Identifying People from Body Motion and Relations in Virtual Reality. In Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems. CHI '19. ACM, New York, NY, USA. [Download Bibtex]
buschek2016chi2.jpg Daniel Buschek, Alexander De Luca and Florian Alt. Evaluating the Influence of Targets and Hand Postures on Touch-based Behavioural Biometrics. In Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems. CHI '16. ACM, New York, NY, USA. [Download Bibtex]
buschek2016chi1.jpg Daniel Buschek, Fabian Hartmann, Emanuel von Zezschwitz, Alexander De Luca and Florian Alt. SnapApp: Reducing Authentication Overhead with a Time-Constrained Fast Unlock Option. In Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems. CHI '16. ACM, New York, NY, USA. [Download Bibtex]
buschek2015chi.jpg Daniel Buschek, Alexander De Luca and Florian Alt. Improving Accuracy, Applicability and Usability of Keystroke Biometrics on Mobile Touchscreen Devices. In Proceedings of the 33rd Annual ACM Conference on Human Factors in Computing Systems. CHI '15. ACM, New York, NY, USA. [Download Bibtex]
buschek2015chiea.jpg Daniel Buschek, Michael Spitzer and Florian Alt. Video-Recording Your Life: User Perception and Experiences. In Proceedings of the 33rd Annual ACM Conference Extended Abstracts on Human Factors in Computing Systems. CHI EA '15. ACM, New York, NY, USA. [Download Bibtex]