Dialerauth: A motion-assisted touch-based smartphone user authentication scheme

This paper introduces DialerAuth - a mechanism which leverages the way a smartphone user taps/enters any “text-independent" 10-digit number (replicating the dialing process) and the hand’s micro-movements she makes while doing so. DialerAuth authenticates the user on the basis of timing differences in the entered 10-digit strokes. DialerAuth provides enhanced security by leveraging the transparent and unobservable layer based on another modality - user’s hand micro-movements. Furthermore, Dialerauth increases the usability and acceptability by utilizing the users’ familiarity with the dialing process and the flexibility of choosing any combination of 10-digit number. We implemented DialerAuth for both data collection and proof-of-concept real-time analysis. We collected, in total ≈10500 legitimate samples involving 97 users, through an extensive unsupervised field experiment, to evaluate the effectiveness of DialerAuth. Analysis using one-class Multilayer Perceptron (MLP) shows a TAR of 85.77% in identifying the genuine users. Security analysis involving ≈240 adversarial attempts proved DialerAuth as significantly resilient against random and mimic attacks. A usability study based on System Usability Scale (SUS) reflects a positive feedback on user acceptance (SUS score = 73.29).