Towards Practical Auditing of Dynamic Data in Decentralized Storage

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

View graph of relations

Related Research Unit(s)

Detail(s)

Original languageEnglish
Number of pages16
Journal / PublicationIEEE Transactions on Dependable and Secure Computing
Online published13 Jan 2022
Publication statusOnline published - 13 Jan 2022

Abstract

Decentralized storage (DS) projects such as Filecoin are gaining traction. Their openness mandates effective auditing mechanisms to assure users that their data remains intact. A blockchain is typically employed here as an unbiased public auditor. While the case for static data is relatively easy to handle, on-chain auditing of dynamic data with practical performance guarantees is still an open problem. Dynamic Proof-of-Storage (PoS) schemes developed for conventional cloud storage are not applicable to DS, since they require large storage proofs and/or large auditor states that are unmanageable by resource-constrained blockchains. To fill the gap, we propose a family of dynamic on-chain auditing protocols that can produce concretely small auditor states while retaining the compact proofs promised by static PoS schemes. Our design revolves around a set of succinct data structures and optimization techniques for index information management. With proper instantiation and realistic parameters, our protocols can achieve 0.25MB on-chain state and 1.2KB storage proof for the auditing of 1TB data, outperforming previous dynamic PoS schemes that are adaptable for DS by orders of magnitude. As another practical contribution, we introduce a data abstraction layer that allows one to deploy the auditing protocols on arbitrary storage systems hosting dynamic data.

Research Area(s)

  • Blockchain, Blockchains, Cloud computing, Costs, Data Dynamism, Data Integrity Auditing, Data structures, Decentralized Storage, Indexes, Protocols, Security