Cryptology ePrint Archive: Report 2020/865

Agora: A Privacy-Aware Data Marketplace

Vlasis Koutsos and Dimitrios Papadopoulos and Dimitris Chatzopoulos and Sasu Tarkoma and Pan Hui

Abstract: We propose Agora, the first blockchain-based data marketplace that enables multiple privacy-concerned parties to get compensated for contributing and exchanging data, without relying on a trusted third party during the exchange. Agora achieves data privacy, output verifiability, and atomicity of payments by leveraging cryptographic techniques, and is designed as a decentralized application via smart contracts. Particularly, data generators provide encrypted data to data brokers who use a functional secret key to learn nothing but the output of a specific, agreed upon, function over the raw data. Data consumers can purchase decrypted outputs from the brokers, accompanied by corresponding proofs of correctness. We implement a working prototype of Agora on Ethereum and experimentally evaluate its performance and deployment costs. As a core building block of Agora, we propose a new functional encryption scheme with additional public parameters that operate as a trust anchor for verifying decrypted results.

Category / Keywords: Data marketplace, Functional Encryption, Blockchain

Date: received 10 Jul 2020

Contact author: vkoutsos at cse ust hk

Available format(s): PDF | BibTeX Citation

Version: 20200712:125421 (All versions of this report)

Short URL: ia.cr/2020/865


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