Are Passfaces More Usable Than Passwords? A Field Trial Investigation

  • Sacha Brostoff
  • M Angela Sasse


The proliferation of technology requiring user authentication has increased the number of passwords which users have to remember, creating a significant usability problem. This paper reports a usability comparison between a new mechanism for user authentication — Passfaces — and passwords, with 34 student participants in a 3-month field trial. Fewer login errors were made with Passfaces, even when periods between logins were long. On the computer facilities regularly chosen by participants to log in, Passfaces took a long time to execute. Participants consequently started their work later when using Passfaces than when using passwords, and logged into the system less often. The results emphasise the importance of evaluating the usability of security mechanisms in field trials.


task performance evaluation passwords security human memory 


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Copyright information

© Springer-Verlag London 2000

Authors and Affiliations

  • Sacha Brostoff
    • 1
  • M Angela Sasse
    • 1
  1. 1.Department of Computer ScienceUniversity College LondonLondonUK

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