关键词: 监管区块链（RBC）, 交易区块链（TBC）, 双链式区块链, 智能合约, 零知识证明

Abstract:

Recently, as a decentralized distributed ledger, the blockchain enables people to conduct secure and reliable transactions in an untrustworthy environment, the blockchain has been applied to various fields. However, some problems have gradually exposed, such as leaking privacy information of users, illegal transactions, lack of effective regulatory, and loopholes in the smart contracts market. Aiming at the illegal transaction of blockchain, the concept of regulatory blockchain is proposed, and a double-chain structure that can effectively supervise blockchain transactions is established, which is Transaction Blockchain（TBC） and Regulatory Blockchain（RBC）. In order to improve the security of smart contracts, a smart contracts market in the regulatory blockchain is proposed, and a zero-knowledge proof algorithm is designed to verify smart contracts function. Theoretical and data analysis show that the double-chain structure is highly efficient and scalable. The experimental result demonstrates that the classification accuracy of machine learning algorithms for blockchain transaction data can reach 95.0%, and proves the feasibility of zero-knowledge proof.

Key words: Regulatory Blockchain（RBC）, Transaction Blockchain（TBC）, double-chain blockchain, smart contract, zero-knowledge proof