Blockchain Transaction Anonymity and Identity Authentication Security Based on Zero-Knowledge Proof Algorithm

Abstract

This paper proposes a framework that integrates zero-knowledge proofs (ZKPs) and verifiable credentials (VCs) to achieve the synergistic optimization of transaction privacy and trusted identity authentication. First, a pseudonymous transaction protocol based on zk-SNARKs (zero-knowledge succinct non-interactive arguments of knowledge) is designed. The R1CS constraint system is used to construct a circuit that hides the transaction amount and address, resulting in a proof that takes up only 1.5 KB. Second, the W3C standard VC is introduced to enable off-chain identity attribute authentication. Users generate a “credential validity proof” using ZKPs and upload the proof along with the transaction to the chain. Finally, smart contracts verify the dual proofs, using Merkle tree aggregation to reduce verification overhead. An innovative “attribute-bound anonymous transaction” model is proposed to dynamically decouple transaction and identity attribute verification. Deployment on the Ethereum testnet demonstrates that this scheme reduces transaction correlation to approximately 0.3 %. Groth16 achieves a throughput of 142 transactions per second (TPS) in 798 ms at a scale of 200,000 gates.