Cloud computing is a fast-growing technology which supplies scalable, innovative, and efficient business models. However, cloud computing is not fully trusted, and the security of the data outsourced in cloud storage needs to be guaranteed. One of the hottest issues is how to ensure the integrity of the data in cloud storage. Until now, many researchers have proposed lots of provable data possession (PDP) schemes to deal with the problem of data integrity audition. Nevertheless, very little effort has been devoted to preserve the data uploader’s privacy while auditing the integrity of data shared in a group. To overcome the shortcoming, we propose a novel certificateless PDP protocol to efficiently audit the integrity of data shared in a workgroup with user privacy preserving. Due to the inherent structural advantage of the certificateless crypto mechanism, our PDP scheme eliminates the key escrow problem and the certificate management problem simultaneously. Moreover, the audition process in our scheme does not need any user’s identity which helps to keep the anonymity of data uploader. We give for our scheme a detailed security proof and efficiency analysis. Experiment results of performance evaluation demonstrate that our new scheme is very efficient and feasible.
Public Proof of Retrievability Scheme against Active Attack in Cloud Storage