GRAPHICAL PASSWORDS FOR PROVIDING A NEW SECURITY PRIMITIVE

Abstract

CAPTCHA (Completely Automated Public Turing Test to distinguish between computers and human) is a computer program which humans can pass but computer programs cannot pass. A new technology is built over the captcha called graphical captcha which eliminates dictionary attacks and hence more secure. With the hybrid use of CAPTCHA and graphical password, one can address a number of security problems such as relay attack and online guessing attacks. Shoulder surfing attacks can also be addressed with the help of dual view technology. CaRP (Captcha as a graphical password) is not a cure all to all attacks but it stipulates security and usability to legitimate and authenticated users in real time applications. In the proposed concept, we present exemplary CaRPs built on both text Captcha and image-recognition Captcha. A user selects random and difficult images as passwords for reducing the guessing attack.