Secure Cloud Storage with Deduct-Based Deduplication Using Proof of Ownership and Proof of Storage

Abstract

Cloud computing has revolutionized data storage by offering scalable, cost-efficient, and on-demand resource management. A key optimization technique in cloud environments is data deduplication, which eliminates redundant copies of identical files and stores only a single instance to improve storage efficiency and reduce operational costs. Despite its advantages, deduplication introduces security concerns related to file ownership, privacy preservation, and data integrity, particularly when multiple users attempt to claim access to the same content. To address these issues, existing systems implement Proof of Ownership (PoW), a cryptographic protocol that verifies whether a user legitimately possesses a file before granting access. In PoW-based schemes, users generate cryptographic proofs derived from file contents instead of re-uploading the entire file, thereby conserving bandwidth and computational resources. However, PoW provides only static verification at a single point in time, making it vulnerable to hash-based attacks if adversaries obtain file hashes. To overcome this limitation, the proposed framework integrates Proof of Storage (PoS) with PoW to enable continuous and dynamic ownership verification. PoS periodically challenges users to prove ongoing possession of stored data, thereby enhancing security. This hybrid PoW–PoS approach strengthens data protection, ensures persistent ownership validation, and maintains storage efficiency in deduplicated cloud environments.