International Journal of Computer Science Issues
Authentication is one the most important security primitive. Password authentication is most widely used authentication mechanism. Users generally use characters as passwords but text-based passwords are difficult to remember and if they are easy to remember then they are vulnerable to various kinds of attacks and are predictable. To address these authentication problems, a new alternative authentication method have been proposed using pictures as passwords. It is supported by the fact that Human brain has remarkable ability to remember thousands of images with detail. Whereas it difficult to keep text in memory. In Graphical authentication user performs some events on pictures like clicking, dragging, moving mouse etc. In this paper, the authors conduct a comprehensive survey of the existing graphical authentication systems.