Protection against Password Guessing Attacks Using Persuasive Cued Click Point

Graphical passwords are an alternative to alphanumeric passwords in which users click on images to authenticate themselves rather than type alphanumeric strings. We have developed one such system, called persuasive cued click point, and evaluated it with human users. The results of the evaluation were promising With respect to memorability of the graphical password. In this study we expand our human factors testing by studying two issues: the effect of tolerance or margin of error, in clicking on the password points and the effect of the image used in the password system. In this paper study, results show that accurate memory for the password is strongly reduced when using a small tolerance (10*10 pixels) around the user’s password points. This may occur because users fail to encode the password points in memory in the precise manner that is necessary to remember the password over a lapse of time. In our image study we compared user performance on four everyday images. The results indicate that there were few significant differences in performance of the images. This preliminary result suggests that many images may support memorability in graphical password Systems.