For several decades, researchers have been exploring the potential of using biometric typing keypads for user identification and authentication, to improve security within organizational networks. However, there has been a lack of broad and rigorous testing on how the technology performs under various field conditions. We conducted a 3 x 1 factorial experiment over a 30-day period to investigate how variations in individual typing patterns over time affected the accuracy of keystroke authentication in biometric systems. We found that individual typing patterns varied over time, especially in terms of the individual’s typing duration time. This variance in turn affected the accuracy of the biometric keypad. Furthermore, we found no linear correlation between the variation in typing patterns and the resulting deterioration in accuracy. This suggests that the design of automated, self- adjusting algorithms to compensate for change in individual typing patterns is more complex than previously thought. These findings raise doubts on the reliability and hence suitability of typing biometrics especially for critical authentication systems. Rather, we suggest that typing biometrics would be more suitable in niche fields like continuous background authentication, as a secondary authentication layer and for personalization systems.

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