PIR-DSN: A Decentralized Storage Network Supporting Private Information Retrieval

2025-12-08

AI Summary

Decentralized storage networks (DSNs) inherently risk user privacy leakage during file retrieval. To address this, we propose the first private information retrieval (PIR) integration protocol compatible with both single- and multi-server settings. Our approach introduces a secure mapping mechanism that compresses sparse file identifiers into compact integer indices, and combines multi-miner redundant replication with publicly verifiable operations to ensure privacy robustness and data integrity under Byzantine adversarial conditions. Experimental evaluation shows that upload and deletion overheads match those of state-of-the-art industrial DSNs, while retrieval throughput approaches that of non-private baselines—significantly outperforming existing PIR-DSN schemes. This work presents the first efficient, robust, and publicly verifiable PIR deployment in real-world decentralized storage, enabling practical privacy-preserving file access for sensitive applications.

Technology Category

• Search and Optimization: Distributed Search
• Machine Learning: Privacy
• Data Mining & Knowledge Management: Data Compression

Application Category

• Security and Privacy: Privacy-enhancing technologies
• Responsible Web: Data and user privacy-enhancing technologies for the Web
• User Modeling, Personalization and Recommendation: User privacy protection in personalized systems

Abstract

Decentralized Storage Networks (DSNs) are emerging as a foundational infrastructure for Web 3.0, offering global peer-to-peer storage. However, a critical vulnerability persists: user privacy during file retrieval remains largely unaddressed, risking the exposure of sensitive information. To overcome this, we introduce PIR-DSN, the first DSN protocol to integrate Private Information Retrieval (PIR) for both single and multi-server settings. Our key innovations include a novel secure mapping method that transforms sparse file identifiers into compact integer indexes, enabling both public verifiability of file operations and efficient private retrieval. Furthermore, PIR-DSN guarantees Byzantine-robust private retrieval through file replication across multiple miners. We implement and rigorously evaluate PIR-DSN against three prominent industrial DSN systems. Experimental results demonstrate that PIR-DSN achieves comparable overhead for file upload and deletion. While PIR inherently introduces an additional computational cost leading to higher retrieval latency, PIR-DSN maintains comparable throughput. These findings underscore PIR-DSN's practical viability for privacy-sensitive applications within DSN environments.

Problem

• Addresses privacy vulnerability in decentralized storage file retrieval
• Integrates Private Information Retrieval for single and multi-server settings
• Ensures Byzantine-robust private retrieval via file replication across miners

Innovation

• Integrates Private Information Retrieval into decentralized storage networks
• Uses secure mapping for verifiable and efficient private file retrieval
• Ensures Byzantine-robust privacy via file replication across multiple miners