Encryption Domain Text Retrieval

摘要

This paper proposes efficient indexing and querying services on encrypted user documents stored in the cloud. We develop few sophisticated techniques to ensure that any network intruder or even the cloud service provider itself is oblivious to both user data content and the type of operations performed over the data. All data operations, including encryption and decryption of data are performed in the client environment, thereby guaranteeing complete data security. By providing, such a secure system to store and access data on the cloud, end users will be free of any security concerns and hence can easily migrate their data to the cloud. We have implemented an Encryption Domain Text Retrieval (EDTR) System that has a server positioned in the cloud to provide indexing, storage and querying services and a client tool on the end user system that processes the user documents. In order to enable the cloud server to work on encrypted data, the client tool orchestrates the user data into sets of keywords which are again encrypted. We further provide an unique measurement technique to identify unfaithful execution of user requested services by the cloud service provider. Our experiments demonstrate the practical applicability of such a sophisticated system. Though we logically explain the security implications and how the EDTR system overcomes typical cloud security issues, we do not focus on providing concrete, theoretical security proofs.