Cloud Outsourced Key with Identity Based Encryption

Abstract

Remote data integrity checking is of crucial importancein cloud storage. It can make the clients verify whethertheir outsourced data is kept intact without downloading thewhole data. In some application scenarios, the clients have tostore their data on multi-cloud servers. At the same time, theintegrity checking protocol must be efficient in order to savethe verifier’s cost. From the two points, we propose a novelremote data integrity checking model: ID-DPDP (identity-baseddistributed provable data possession) in multi-cloud storage. Theformal system model and security model are given. Based onthe bilinear pairings, a concrete ID-DPDP protocol is designed.The proposed ID-DPDP protocol is provably secure under thehardness assumption of the standard CDH (computational Diffie-Hellman) problem. In addition to the structural advantage ofelimination of certificate management, our ID-DPDP protocol isalso efficient and flexible. Based on the client’s authorization,the proposed ID-DPDP protocol can realize private verification,delegated verification and public verification.