Citation
Chow, R.; Golle, P.; Jakobsson, M.; Wang, X.; Wang, L. Making CAPTCHAs clickable. Ninth Workshop on Mobile Computing Systems and Applications (HotMobile 2008); 2008 February 25-26; Napa, CA. NY: ACM; 2008; 91-94.
Abstract
We show how to convert regular keyboard-entry CAPTCHAs into clickable CAPTCHAs. The goal of this conversion is to simplify and speed-up the entry of the CAPTCHA solution, to minimize user frustration and permit the use of CAPTCHAs on devices where they would otherwise be unsuitable. We show how to obtain a secure clickable CAPTCHA that is well suited for use on cell phones. We support the practical viability of our approach by results from a user study, and an analysis of its security guarantees.