安全组播中的密钥树最优结构

组播常用来对一组用户发送数据．为了保障安全性，安全组播使用组内共享的加密密钥对组内通信进行加密．因为组成员关系的动态性，有效进行组密钥管理成为安全组播通信性能的关键．本文研究了组密钥管理的密钥树结构，并提出了一种新的基于组成员更新概率的最优密钥树结构．这种结构能够进一步减少系统开销．实验结果表明这种密钥树结构要优于其它基于组成员更新概率的密钥树结构，同时理论分析给出了这种结构的平均更新代价的取值范围．

Optimal Key Tree Structure in Secure Multicast

Multicast is often used to deliver packets to a group of users. To ensure security, a group key is used in secure multicast to encrypt group communication. Because of the dynamic group membership, the performance of key management becomes the core factor of secure multicast. This paper investigates key tree structure for group key management and proposes a new optimal key tree structure based on member updating probabilities. With this optimal tree structure, system costs can be properly reduced.It is verified by the experiment results that this key tree structure is better than other key tree structures based on member updating probabilities, and the bounds of this structure's average updating cost are analyzed.