一种去中心化的隐私保护匿名问卷方案

针对传统匿名问卷系统不能抵抗合谋攻击及公布数据时无法保护用户隐私的问题，提出一种新的隐私保护匿名问卷方案。引入少数合谋的问卷工作节点集群，利用门限签名技术为用户进行注册，并以门限签名为问卷生成用户列表，从而抵抗合谋攻击，同时将用户回应进行同态加密上传至公开防篡改平台抵抗数据抵赖，采用差分隐私技术并借助安全多方计算技术输出隐私保护的问卷归总结果。在此基础上，将问卷过程融入零知识证明技术，保证密文的健壮性及方案的正确性。性能分析结果表明，该方案的安全模型满足匿名性、验证性、机密性及隐私保护性，与ANONIZE、Prio等方案相比，在合谋攻击抵抗、隐私保护方面更有优势，且在时间和存储开销上符合实际应用需求。

A Decentralized Scheme for Privacy-Preserving Anonymous Surveying

The existing anonymous survey systems usually fail to resist collusion attacks or protect user privacy when publishing data.To address the problem, this paper proposes a new privacy-preserving anonymous survey scheme.The scheme introduces a work node cluster based on minority collusion for surveying, and employs the threshold signature technology to register users.The threshold signatures are also used to generate a user list for surveying to resist collusion attacks.At the same time, the user response is homomorphically encrypted and uploaded to the public tamper-proof platform to resist data denial.By using the differential privacy technology and the secure multi-party computing technology, the privacy-preserving summarized results of the survey are obtained.On this basis, the zero-knowledge proof technology is used for surveying to ensure the robustness of the ciphertext and the correctness of the scheme.Performance analysis results show that the security model of this scheme satisfies anonymity, verification, confidentiality and privacy protection.Compared with ANONIZE, Prio and other schemes, it has more advantages in collusion attack resistance and privacy protection, meeting the actual application requirements in time and storage overhead.