Blockchain Enabled Data Trading with User Consent

Data trading is ubiquitous in today's Internet. User data is often sensitive in nature, for example, medical records and sensitive health related information. Present data trade often does not capture the owner's consent or allow tracking of the sale of her data. Even during a sale, fairness is not guaranteed and both the data owner and the data buyer remains at risk of being cheated. In this paper, we propose an end-to-end protocol to trade sensitive information addressing the key issues of consent, traceability and fairness. We use blockchain as the arbitrator and tamper-resistant log. We implement a prototype of our protocol on Ethereum and show that our proposed solution is practical.