4-STAGE GRAPHICAL PASSWORD AUTHENTICATION SCHEME FOR CLOUD

Cloud computing is the fastest growing part of IT industry as it provides dynamic and scalable services to the user in a cost-efficient way. Unfortunately, cloud is also vulnerable to various attacks as it is based on Internet. Cloud service providers offering different types of services delivered over the internet without any delay are governed by Service Level Agreements, which are entered between the vendor and the user. Authentication still remains an issue that is vulnerable to shoulder surfing, guessing attack and various types of other attacks. There is a need to have a proper password checking mechanism so that the degree of vulnerability in the process of authentication gets reduced. In this paper, an effort has been made to present a novice algorithm for the authentication process which totally alleviates the problems of shoulder surfing and guessing attacks. This algorithm works in four stages. If all the four stages are through successfully then one can access the cloud securely.