Applicability of keystroke dynamics as a biometric security feature for mobile touchscreen devices with virtualised keyboards

摘要

Touchscreen-based smartphones with virtualised QWERTY keyboards are becoming increasingly popular and by and by displace the old numerical keypads of normal cellular phones. On traditional desktop computer keyboards, which basically feature the same layout as the virtualised smarthpone keyboards, keystroke dynamics analysis (KDA) algorithms have long since been successfully used as an additional factor for user authentication. However the question remains whether the algorithms used for desktop computers also achieve good results on touchscreen-based devices. This paper presents the results of an experimental user study on the performance of a KDA algorithm for desktop computers applied on a touchscreen-based smartphone. The results achieved are far inferior than those achieved with a desktop computer keyboard. As will be shown, standard typing characteristics (like time between two key events) which provide good results for user authentication on desktop computers are not sufficient for building a successful KDA algorithm for virtual touchscreen keyboards. Hence, this paper also identifies additional features that could be incorporated in such an algorithm in order to improve the accuracy of KDA on touchscreen-based mobile devices.