Preserving Privacy by Enhancing Security inCloud

Abstract

Cloud computing is emerging as a prevalent data interactive paradigm to realize users’ data remotely stored in an online cloud server. Cloud services provide more benefits for the users to enjoy the on-demand cloud applications without considering the local limitations. When accessing the data, many users may be in a collaborative relationship, and thus sharing of is significant to achieve productive benefits. The present solutions for security focuses on the authentication to realize that a user’s privative data cannot be accessed if it is found to be unauthorized, but it eliminates a subtle privacy issue during a user challenging the cloud server to request other users when the data being shared. The challenge is the request for accessing reveals the user’s privacy no matter whether it has got the data access permissions. The distributed privacy-preserving authentication protocol (SAPA) which is authority based to address above privacy issue for cloud storage. shared authority based privacy-preserving authentication protocol (SAPA) to address above privacy issue for cloud storage. In the SAPA, 1) shared access is achieved by anonymous access request matching mechanism with security and privacy considerations 2) attribute based access control is adopted to realize that the user can only access its own data fields; 3) proxy re-encryption is applied by the cloud server to provide data sharing among the many users. Meanwhile, universal compos ability (UC) model is established to prove that the SAPA theoretically has the correct design. This clearly shows that the proposed protocol realizing privacy-preserving data access authority sharing is impressive for multiple users collaborative cloud applications.