Touchstroke: Smartphone User Authentication Based on Touch-Typing Biometrics

Smartphones are becoming pervasive and widely used for a large variety of activities from social networking to online shopping, from message exchanging to mobile gaming, to mention just a few. Many of these activities generate private information or require storing on the phone user credentials and payment details. In spite of being so security and privacy critical, smartphones are still widely protected by traditional authentication mechanisms such as PINs and passwords, whose limitations and drawbacks are well known and documented in the security community. New accurate, user-friendly and effective authentication mechanisms are required. To this end, behavior-based authentication has recently attracted a significant amount of interest in both commercial and academic contexts.

This paper proposes a new bi-modal biometric authentication solution,

Touchstroke

, which makes use of the user’s hand movements while holding the device, and the timing of touch-typing(Touch-typing is the act of typing input on the touchscreen of a smartphone.) when the user enters a

text-independent

4-digit PIN/password. We implemented and tested the new biometrics in real smartphones. Preliminary results are encouraging, showing high accuracy. Thus, our solution is a plausible alternative to traditional authentication mechanisms.