近年来随着对区块链交易隐私保护的加强，审计区块链交易和追踪非法交易者身份变得更加困难。为此，提出可审计且可追踪的区块链匿名交易方案。利用Elgamal加密、数字签名和改进的隐地址等技术来实现交易内容、交易发送方身份和交易接收方身份三方面的隐私保护。引入审计方和监管方两个角色以实现权力分配，当审计方审计到交易双方存在非法交易时，向监管方发送带有签名的追踪身份请求。签名验证通过后，监管方可利用收到的追踪密钥和个人的监管密钥追踪到交易双方的身份。该方案实现了交易的匿名性、可审计性和身份的可追踪性。仿真实验结果表明该方案的审计效率较高。
In recent years, with the strengthening of privacy protection for blockchain transactions, it has become more difficult to audit blockchain transactions and track the identity of illegal traders. For this reason, an auditable and traceable blockchain anonymous transaction scheme is proposed in this paper. Elgamal encryption, digital signature and improved hidden address technologies are used to realize the privacy protection of the transaction content and the identities of transaction senders and transaction receivers, and realize the distribution of power by introducing two roles of auditor and regulator. When an illegal transaction is audited, auditor sends a tracking identity request with signature to the regulator. After the signature is verified, the regulator can use the received tracking key and the personal key to trace the identities of both parties to the transaction. This scheme satisfies the anonymity, auditability and identity traceability of transactions. Simulation experiment results show the high audit efficiency of the scheme.
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