Abstract: This paper introduces image based CAPTCHA to protect user data or unauthorized access of information. Here the password is created from images and text password. The Current system is based on only text password but it has some disadvantages like small password mostly used and easy to remember. This type of password is easy to guess through different attack i.e. dictionary attack and brute force attack. We are proposing a new system which uses multiple servers, enabling added level of security to the existing authentication, thereby providing access to the database. As this is a technique based on recognition of graphical background more security is achieved as well as easy to remember.
Keywords: CAPTCHA, Password, dictionary attack, brute force attack, graphical password, multiple server.