DART: Distributed Zero Knowledge Data Auditing with Retrievability for Blockchain-Based Decentralized Storage Networks

The advent of blockchain technology has led to the development of decentralized storage networks, revolutionizing the way data are stored and accessed and offering advantages such as cost-effective services, improved data sovereignty, and resistance to censorship. However, nodes of decentralized storage networks cannot be fully trusted and data stored in them may not be as secure and intact as claimed. Therefore, how to guarantee the storage service quality in decentralized storage networks is still a major problem to be solved. In this paper, we propose DART, a distributed zero knowledge data auditing scheme for blockchain-based decentralized storage networks, periodically authenticating both the integrity and the retrievability of data in decentralized storage networks. We design an efficient integrity auditing protocol for decentralized nodes based on distributed zero knowledge protocols, which improves the performance of auditing whilst maintaining low cost with zero knowledge protocols. Furthermore, we introduce the erasure code in decentralized storage networks to support data retrievability across decentralized nodes. By leveraging accumulator techniques to design a dual accumulation strategy, we build a batch verification approach to improve the communication and computation efficiency in data retrieval checking. We analyze the security of DART under the random oracle model and conduct extensive experiments to evaluate its performance. Experimental results affirm that DART outperforms state-of-the-art approaches in decentralized storage networks, reducing the overhead in both the storage and verification phases by more than 70%. Moreover, this performance advantage becomes increasingly pronounced with larger file sizes, underscoring the scalability and practicality of DART.