Assessment of the Usability and Acceptability of Passface Authentication Mechanism on Android Phones

The research aims at assessing usability and acceptability of Passfaces authentication scheme. Passfaces is an authentication scheme that allows users to select facial images of their choice as pass code to gain access to their phones, computers, or other computing resources. We have developed a special android app that simulated the Passfaces technology. We run experiments with 232 volunteers recruited via our social media contacts. The users were asked to create Passfaces passwords of size 4, 5, 6, and 8. The results reveal that Passfaces of size 4 is more usable with least average authentication time and minimal errors. Overall, 80% of the volunteers could authenticate in the first attempt, about 10% and 3% authenticated in the second and third attempts, respectively; and only 7% failed to authenticate completely.