ARTICLE INFO In this paper we propose authentication schemes which consist of graphical password based captchas. It consists of both a captcha and a graphical password schemes. To boost the security aspect to the next level, we contribute some captcha schemes that provide user high security at time of login. Our system provides choice of various authentication schemes to user at time of login. Along with these schemes session based authentication is also provided which will protect system from

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... nauthorized access. We extend the use of captcha as human present recognition as well as graphical password hence it provides all benefits of captcha and make system more powerful from security point of view.