一种基于树结构的分布式组密钥协商协议

提出了一种基于带有认证功能的组密钥协商（BD）协议和树结构的分布式组密钥协商（T-BD）协议。协议将加入认证功能的BD协议与逻辑密钥树相结合，尽管在协商开始时增加了一定数量的通信和计算开销，但协议能够保证内部节点的诚实性，抵抗了来自内部节点的主动攻击。由于协议具有认证功能，能够检测出协议内部发动攻击的恶意节点，而且减小了成员关系变动时的通信量和计算量，能够高效地处理成员加入和退出。由于原有协议的认证功能，使得内部恶意节点不能实施主动攻击。经计算协议在通信轮效率和模指数运算方面都较原协议有明显减少，可扩展性非常高，适合于目前流行的P2P应用的组密钥协商。

An Improved Tree-based Distributed Group Key Agreement Protocol

A distributed group key agreement protocol based on authenticated-BD and logical tree,namely T-BD,was proposed.Although the communication and computation costs are increased at the beginning of the proposed protocol,the protocol can guarantee honesties of participants and prevent attacks from internal malicious members.Since the protocol has authentication ability,it can detect the internal malicious attackers.And,the communication and computation costs decrease when new members join and leave,dealing with members’ joining and quitting efficiently.As the protocol is constructed on top of authenticated-BD,the internal malicious members can not attack initiatively.Compared with the existing protocols,the proposed protocol has low communication cost and efficient modular exponentiation and is more scalable for distributed P2P application.