Abstract: This research aims to study the existing password schemes and to design and develop a new improved graphical password scheme. CaRP is Captcha as a graphical password. With the hybrid use of CAPTCHA and graphical password it can addresses a number of security problems altogether. In information security, user authentication is a major problem in every system. And for authentication purpose every system depends on password whether it is textual password or graphical password. CAPTCHA is a test build by computer programs which human can pass but computer programs cannot pass. In this paper, we discuss the strengths and limitations of each method and present a combination of CaRP and graphical password scheme which is protected to the common attacks suffered by other authentication schemes.

Keywords: Graphical Password, CaRP, CAPTCHA, Authentication, Security.