A Secure Ownership Verification Model for Accessing Deduplicated Cloud Data

Abstract

Cloud storage platforms commonly use data deduplication to remove repeated file copies and improve storage utilization. While this approach helps reduce storage overhead and network usage, it raises an important security concern: how to confirm that a user requesting access to a deduplicated file is the rightful owner. To address this issue, this paper presents a secure ownership verification model for controlled access to deduplicated cloud data. The proposed method improves access validation by creating a file-specific verification value using both user-related and file-related attributes, such as user credentials, token details, and file tag information. This value is generated during file upload and recomputed whenever a user requests access to the stored file. Access is permitted only when the regenerated value matches the previously stored verification record, thereby preventing unauthorized retrieval. The model was implemented in a cloud environment using C#.NET and deployed on Microsoft Azure, and its performance was evaluated in terms of file access computation time for different file sizes. Experimental results show that the proposed approach outperforms existing methods such as CAE and Dekey by achieving lower computational time while also providing stronger ownership-based access control.