SDS: A Framework for Secure Data Sharing in Database as a Service

Cloud computing is a magic and attractive technology to the single user to large enterprises to store their data. It has less expensive and useful model for enterprise who concentrates more on themes instead of buying products. But, obstacle for the cloud is privacy and unauthorized access of users from internal or external. To achieve the privacy of data from the internal the client stores their sensitive data in the encrypted form. But for the large organizations, the delegated contents are shared by various users. So, we are in the need of an efficient access control mechanisms which coupled with encrypted data to privacy preserving data sharing among the users. In this paper, we present a novel approach to flexible data access control with re-encryption performed by the service provider. The basic design of this process is applying the two-level encryption on the data with access control. The service provider performs the second level encryption with user?s proxy key which is unique to the users. This approach provides the selective authorization on the encrypted data and also provides the flexible access control. Even though it has lot of proxy keys as much of users, no need of key distribution. And also, the user should remember only his secret key. In the end of this paper, we analyze and resolve the solutions for the possible attacks.