Decentralizing Privacy: Using Blockchain to Protect Personal Data

TLDR

Recent surveillance breaches have highlighted the risks of third‑party data control, while Bitcoin shows that decentralized, auditable computing is achievable through a public ledger. The paper proposes a decentralized personal data management system that gives users ownership and control over their data, and outlines future blockchain extensions for broader trusted computing. We implement a protocol that converts a blockchain into an automated, trust‑less access‑control manager, using non‑financial transactions to store, query, and share data. The protocol demonstrates that a blockchain can function as an automated, trust‑less access‑control manager for personal data.

Abstract

The recent increase in reported incidents of surveillance and security breaches compromising users' privacy call into question the current model, in which third-parties collect and control massive amounts of personal data. Bit coin has demonstrated in the financial space that trusted, auditable computing is possible using a decentralized network of peers accompanied by a public ledger. In this paper, we describe a decentralized personal data management system that ensures users own and control their data. We implement a protocol that turns a block chain into an automated access-control manager that does not require trust in a third party. Unlike Bit coin, transactions in our system are not strictly financial -- they are used to carry instructions, such as storing, querying and sharing data. Finally, we discuss possible future extensions to block chains that could harness them into a well-rounded solution for trusted computing problems in society.