Abstract: In the wireless environment, we need to allocate a group key for everyone in the group in some kinds of service. An excellent key management schemes can efficiently reduce the communication burden, improve the system performance .In this paper , we analyze the state and the problem of existing key management schemes ,then propose a Logical Key Tree scheme based on physic topology .we design the scheme and evaluate the performance .Simulation results show that this scheme can reduce communication burden efficiently.

Key words: Key tree, Rekey, Multicast security, Wireless network, Key management

摘要： 在无线网络环境中，对一组用户服务时需要为其分配一个组共享密钥。好的密钥管理方案可以极大减少网络通信量，提高系统效率。本文分析了密钥管理的现状及存在的问题，然后提出了一种无线网络中基于物理拓扑结构的逻辑密钥树方案，并对此方案进行设计和性能分析，仿真结果表明此方案能有效减少网络通信量。

关键词: 多播安全, 无线网络, 密钥管理, 密钥分配, 密钥树