User Privileged CAPTCHA as Graphical Password for Multistage Authentication

Abstract

Nowadays, user authentication is one of the important topics in information security. In today’s world the password security is very important. For password protection various techniques are available. Cued Click Points are a click-based graphical password scheme, a cued-recall graphical password technique. Users Click on one point per image for a sequence of images. The next image is based on the previous click-point. The passwords which are easy to memorize are chosen by the users and it becomes easy for attackers to guess it, but the passwords assigned by the strong system are difficult for users to remember. Many current systems have low level security, and even then users often devise insecure coping strategies in order to compensate for memorability and usability problems. Alternatives such as tokens or biometrics raise other issues such as privacy and loss. Various graphical password mechanisms have received considerable attention in response. In this paper describes CAPTCHA authentication is clearly a practical problem. In a new security primitive based on hard AI problems, namely, a novel family of graphical password systems built on top of Captcha technology is call Captcha as graphical passwords.