Evaluating Privacy Technologies in Blockchains for Financial Systems

Sammanfattning: The requirements of privacy have become a necessity in modern-day internet-based applications. This applies from traditional client-server applications to blockchain-based applications. Blockchains being a new domain for application development, the priority towards privacy beyond pseudo anonymity has been lacking. With financial applications built on blockchains entering mainstream adoption, and these applications handling sensitive data of users, it is useful to be able to understand how privacy technologies can help in ensuring that the user’s data privacy is maintained. This project addresses this by taking a simple financial transaction use case and applying various privacy technologies like Data Encryption, Zero-Knowledge Proofs, Trusted Execution Environments. Workflow and Component architecture is proposed for solutions based on these technologies and they are compared to identify which is a feasible solution for the use case. Trusted Execution Environments was concluded to be the best match for the requirements of the use case and Secret Network which is a blockchain built on this privacy technology was evaluated against determined privacy metrics and benchmarks were run to check the performance changes due to using the technology. Based on this analysis, Secret Network was found to be a good solution to handle the provided use case and flexible enough to handle more complex requirements.