在一个大型动态多播群组中,提高组密钥更新效率是一个具有挑战性的难题.分析现存组密钥管理方案的基础上,提出了一种新的组密钥分发协议,该协议使用了异或运算和伪随机函数,使得逻辑密钥树上的密钥呈现出规律性,从而降低了存储量、通信量和计算代价,同时还引入了两个变量将密钥的更新过程分为必要更新与辅助更新两大部分.最后,对协议的安全性进行了分析,并从存储复杂度,通信复杂度和计算量三方面对协议的性能进行了评估. In a large-scale dynamic multicast group, improving the efficiency of group key updating is a challenging challenge.On the basis of analyzing existing group key management schemes, a new group key distribution protocol is proposed, which uses XOR and Pseudo-random functions make the key of the logical key tree appear regular, thus reducing the storage, communication and computational costs, but also introduces two variables to update the key process is divided into Necessary update and auxiliary update.Finally, the protocol security is analyzed, and the performance of the protocol is evaluated from the aspects of storage complexity, communication complexity and computation.