Memory and Motor Processes of Password Entry Error

Abstract

Passwords are tightly interwoven with the digital fabric of our current society. Unfortunately, passwords that provide better security generally tend to be more complex, both in length and composition. Complex passwords are problematic both cognitively and motorically, leading to both memory and motor errors during recall and entry. It is important that we better understand and disentangle the two error sources, as password entry errors can have significant negative consequences, such as being locked out of a critical information system. We present a computational cognitive model of password recall and typing, with memory and motor errors each contributing to password entry error. With this synthesis we can study human-computer interaction issues involving the usability of computer access control systems, specifically the password as an authentication mechanism. Ultimately we hope to make science-based recommendations for password policies that promote the use of passwords that are more usable.