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David Aspinall

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Publications by David Aspinall (bibliography)

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2009
 
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Just, Mike and Aspinall, David (2009): Personal choice and challenge questions: a security and usability assessment. In: Proceedings of the 2009 Symposium on Usable Privacy and Security 2009. p. 8.

Challenge questions are an increasingly important part of mainstream authentication solutions, yet there are few published studies concerning their usability or security. This paper reports on an experimental investigation into user-chosen questions. We collected questions from a large cohort of students, in a way that encouraged participants to give realistic data. The questions allow us to consider possible modes of attack and to judge the relative effort needed to crack a question, according to an innovative model of the knowledge of the attacker. Using this model, we found that many participants were likely to have chosen questions with low entropy answers, yet they believed that their challenge questions would resist attacks from a stranger. Though by asking multiple questions, we are able to show a marked improvement in security for most users. In a second stage of our experiment, we applied existing metrics to measure the usability of the questions and answers. Despite having youthful memories and choosing their own questions, users made errors more frequently than desirable.

© All rights reserved Just and Aspinall and/or ACM Press

 
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Jul 31

Design is the art of gradually applying constraints until only one solution remains.

-- Unknown

 
 

Featured chapter

Marc Hassenzahl explains the fascinating concept of User Experience and Experience Design. Commentaries by Don Norman, Eric Reiss, Mark Blythe, and Whitney Hess

User Experience and Experience Design !

 
 

Our Latest Books

Kumar and Herger 2013: Gamification at Work: Designing Engaging Business Software...
by Janaki Mythily Kumar and Mario Herger

 
Start reading

Whitworth and Ahmad 2013: The Social Design of Technical Systems: Building technologies for communities...
by Brian Whitworth and Adnan Ahmad

 
Start reading

Soegaard and Dam 2013: The Encyclopedia of Human-Computer Interaction, 2nd Ed....
by Mads Soegaard and Rikke Friis Dam

 
Start reading
 
 

Help us help you!