Cross Keyboard Keystroke Dynamics

Keystroke Dynamics is a biometric modality that is used for recognition of a person based on the typing rhythm on a keyboard. Keystroke Dynamics is a behavioural biometric and it is known that behaviour of a person can change when external conditions change. In most research the focus is on performance of the Keystroke Dynamics system under fixed conditions, while change of conditions has not received a lot of attention. In this paper we will specifically consider what happens if the user changes keyboards. We will focus on the performance of a system if a user enrolls using one keyboard, but then later authenticates using another type of keyboard. Our findings show that the performance of the Keystroke Dynamics system under such circumstances, in a small scale experiment, can lead to some deteriorated (of up to 8.10%) but also to a small gain (of up to 0.24 %). We found that the optimal solution is actually to create a reference based on a mixture of typing on both keyboards.