Abstract:

Security issues exists in blockchain system since the validity of transactions is based on the public verification of the ledger. While current research usually overemphasizes privacy, causing blockchain out of regulation in practical applications. The way of ensuring the privacy of user information and enabling users to be tracked by specific supervisors on the blockchain is worth discussing. Based on zero-knowledge proof, stealth address and ring signature, a traceable privacy protection scheme for blockchain ledger is proposed, which prevents ordinary users from reducing the anomymity and enables regulator to decrypt the transaction messages. By using traceable zero-knowledge proofs, traceable stealth address and traceable ring signatures, the privacy of the blockchain ledger is enhanced and the blockchain is under regulation. Theoretical analysis proves the strong security and traceability of the scheme. The simulation experiment demonstrates that the scheme has the strong anonymity and will not significantly affect the performance of the traditional blockchain.

Key words: blockchain, privacy protection, traceability, zero-knowledge proof

摘要：

由于区块链中交易的有效性建立在账本公开验证的基础上，这带来了隐私保护的安全问题。目前的研究成果往往过度强调隐私性，使得区块链在实际应用中不受监管。如何在区块链上既保证用户信息的隐私性又使得用户能够被特定监管人所追踪是一个值得研究的问题。基于零知识证明、隐身地址技术和环签名，提出了一种可追踪的区块链账本隐私保护方案。通过使用可追踪的零知识证明、可追踪的隐身地址和可追踪的环签名，使得一般用户无法通过分析历史账本降低匿名性，同时管理者能够解密交易信息。该方案增强了区块链账本的隐私性，也保证了区块链能够被监管。理论分析证明了方案拥有较强的安全性和可追踪性。仿真实验结果表明方案具有强匿名性，且不会对传统区块链的性能带来显著影响。

关键词: 区块链, 隐私保护, 可追踪性, 零知识证明