后疫情时代将群组应用推向前台，应用的飞速发展势必提出更高的安全要求。组密钥协商协议为群组应用提供安全保护，然而已有的方案缺乏对用户匿名性的研究。.针对这个问题，本项目拟从三个方面研究具有匿名性的组密钥协商协议：（1）针对对称的组密钥协商协议无法实现条件匿名性的问题，提出具有条件匿名性的对称的组密钥协商协议，基于动态身份实现条件匿名性，基于自验证公钥体制、Schnorr签名和Just-Vaudenay协议实现安全性，并在可证明安全理论框架下证明条件匿名性；（2）针对非对称的组密钥协商协议无法实现匿名性的问题，利用基于属性的签名在这类协议中实现匿名性和不可链接性；（3）针对（2）中方法计算效率低的缺陷，提出进一步提高协议效率的方法，包括引入在线/离线签名技术及无双线性对的基于属性的聚合签名算法。.研究成果将满足群组通信不断增长的隐私保护需求，有力支撑群组应用的发展。

The post pandemic era will witness the prosperity of group-based applications, and the rapid development of these applications is bound to put forward higher security requirements. Group key agreement protocols provide security protection to group-based applications, however, existing ones lack the research on anonymity..To solve this problem, this project intends to investigate the group key agreement protocols with anonymity in three aspects. (1) Propose a group key agreement protocol with conditional privacy. The proposal realizes conditional privacy based on dynamic identity, realizes security based on self-certified public key cryptography, Schnorr Signature and Just-Vaudenay Protocol, and proves the conditional privacy in the framework of provable security theory. (2) Propose an asymmetric group key agreement protocol with anonymity. The proposal realizes anonymity and unlinkability based on attribute-based signatures. (3) Improve the efficiency of the proposal in (2) based on online/offline signatures and pairing-free attribute-based aggregate signatures. .The results of this project will satisfy the increasing privacy-protection requirements of group-based applications, and support their development strongly.