A Secure Group Data Access Protocol with Provable Data Possession for Cloud Environment

Cloud-based data storage service has provided a lucrative option for organizations and individual users to store and manipulate their data with a relatively lower cost than traditional data storage approach. However, data stored in a cloud are vulnerable to loss and corruption caused by hardware and software failures, and human errors through interactive online data handling activities. Therefore, authenticity verification on users before granting data access rights has emerged as a critical process for cloud-based data storage service. Current approaches focus only on data owned by individual users. To address access security on cloud-based data shared within a group of users, a data access verification protocol for group users is proposed in this paper. In addition, security analysis is conducted for the proposed protocol to evaluate its security strength.