Title
Designing human friendly human interaction proofs (HIPs)
Abstract
HIPs, or Human Interactive Proofs, are challenges meant to be easily solved by humans, while remaining too hard to be economically solved by computers. HIPs are increasingly used to protect services against automatic script attacks. To be effective, a HIP must be difficult enough to discourage script attacks by raising the computation and/or development cost of breaking the HIP to an unprofitable level. At the same time, the HIP must be easy enough to solve in order to not discourage humans from using the service. Early HIP designs have successfully met these criteria [1]. However, the growing sophistication of attackers and correspondingly increasing profit incentives have rendered most of the currently deployed HIPs vulnerable to attack [2,7,12]. Yet, most companies have been reluctant to increase the difficulty of their HIPs for fear of making them too complex or unappealing to humans. The purpose of this study is to find the visual distortions that are most effective at foiling computer attacks without hindering humans. The contribution of this research is that we discovered that 1) automatically generating HIPs by varying particular distortion parameters renders HIPs that are too easy for computer hackers to break, yet humans still have difficulty recognizing them, and 2) it is possible to build segmentation-based HIPs that are extremely difficult and expensive for computers to solve, while remaining relatively easy for humans.
Year
DOI
Venue
2005
10.1145/1054972.1055070
CHI
Keywords
Field
DocType
human friendly human interaction,early hip design,automatic script attack,segmentation-based hips,computer attack,human interactive proofs,particular distortion parameter,development cost,script attack,computer hacker,renders hips,evaluation,computer vision,profitability,human perception,turing test
World Wide Web,Attack,Computer security,Computer science,Hacker,Human interaction,Mathematical proof,Human–computer interaction,CAPTCHA,Sophistication
Conference
ISBN
Citations 
PageRank 
1-58113-998-5
90
5.39
References 
Authors
9
4
Name
Order
Citations
PageRank
Kumar Chellapilla195162.13
kevin p larson262057.47
Patrice Simard31268621.43
Mary Czerwinski45028421.65