We propose Lockcoin, a secure and privacy-preserving mix service for bitcoin anonymity. We introduce mix servers to provide mix service for user to prevent attackers linking the input address with output address by using blind signature shceme, multisignature scheme. Lockcoin provides anonymity, scalability, bitcoin compatibillity, theft impossibility and accountability. We have proposed a prototype of Lockcoin based on bitcoin test network, experimental results show that our solution is efficient. Lockcoin's source codes are released on github.com/Northeastern-University-Blockchain/Lockcoin.

翻译：本文提出Lockcoin，一种安全且保护隐私的比特币匿名混币服务。我们引入混币服务器，通过采用盲签名方案与多重签名方案为用户提供混币服务，以防止攻击者将输入地址与输出地址关联。Lockcoin具备匿名性、可扩展性、比特币兼容性、防窃取可能性及可追责性。我们基于比特币测试网络提出了Lockcoin的原型系统，实验结果表明该方案具有高效性。Lockcoin的源代码已发布于github.com/Northeastern-University-Blockchain/Lockcoin。