IMPLEMENTATION OF ZERO-KNOWLEDGE PROOF AS A SECURITY AND PRIVACY-PRESERVING METHOD IN ETHEREUM- BASED BLOCKCHAIN NETWORK

• Main Author: Muhammad, Dzaki
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/75261
• Institution: Institut Teknologi Bandung

Blockchain technology emerged to address issues related to data integrity. However, the highly transparent transaction records potentially endanger the privacy of the parties involved, especially concerning traces of identity and relationships between participants. Additionally, the use of blockchain oracles as smart contract connectors to external environments introduces security vulnerabilities in accepting data from untrusted sources. To tackle these problems, a solution is developed using the application of zero-knowledge proofs as a method of security and privacy-preserving for each problem in Ethereum-based blockchain. The solution to preserve privacy in layer-1 blockchain transaction records involves the implementation of ZK-Rollup method, while the solution to enhance security in accepting blockchain oracle data is through the zkOracle method. This final project implements the ZK-SNARK Prover, Aggregator, Oracle Verifier Contract, and L2 Verifier Contract components to support the realization of these solutions. Evaluation of the solution's implementation against various testing scenarios indicates that the solution successfully enhances the security of the blockchain oracle data acceptance process and preserve privacy in layer-1 blockchain transaction records using the implemented zero-knowledge proof circuit. Out of 12 functional testing scenarios, only 1 scenario resulted in incorrect output. All other outputs from integration testing scenarios demonstrate that the solution is well integrated with other components in the capstone project. However, some residual risks from the implemented solution are identified based on the testing results. At the end of this final project, several suggestions for further development or research are provided to address these residual risks.