zKDET: A Traceable and Privacy-Preserving Data Exchange Scheme based on Non-Fungible Token and Zero-Knowledge

With the advent of the Big Data era, industry, business and academia have developed various data exchange schemes to make data more economically beneficial. Unfortunately, most of the existing systems provide only one-time data exchanges without the ability to track the provenance and transformations of datasets. In addition, existing systems encrypt the data to protect data privacy, which hinders demanders from verifying the correctness of the data and evaluating its value. To provide data traceability and privacy while ensuring fairness during data exchanges, we design and implement zKDET, a traceable data exchange scheme based on non-fungible token and zero-knowledge, which is able to (i) track all transformations of data during their lifecycle and record them on the blockchain; (ii) provide zero-knowledge proofs to securely guarantee that all complex transformations and data contents are correct and meet specific requirements; and (iii) warrant exchange fairness and data privacy in public storage platforms. Security analysis and evaluations on zKDET show that it can support traceable data exchange while preserving data privacy and maintaining high throughput despite large data volumes.