【作者】 王芃；

【导师】 何大可；

【作者基本信息】 西南交通大学 ， 密码学， 2007， 硕士

【摘要】 随着无线蜂窝网络的发展与普及，在人们已经不再满足于单一的话音服务。在3G网络即将展开的今天，人们更加希望在无线蜂窝网络中使用如网络电视、在线游戏等高带宽需求的服务。这些服务有一个共同的特点，那就是用户量巨大，分布广泛，在很多情况下，用户群接收的消息内容相同。如果采用单播发送，服务器负担沉重，投资巨大，而且不能保证服务质量。组播是一种群体间进行通信的方式，介于单播和广播之间。无线蜂窝网中提供组播服务在技术方面已经没有什么问题，但是如何保证群组的信息安全却一直是无线组播技术发展中的一个亟待解决的问题。组播密钥管理的主要问题是在组成员变化时如何安全有效地对密钥进行分配。相关的有线网络组播密钥管理方案已经研究多年，较为成熟。但是由于无线网络的一些独有特点，原有的有线网络密钥管理方案不能简单地移植到无线网组播中来。本文通过对目前存在的组播密钥管理方案进行详细的研究分析，提出了一种改进方案，它融合了stateful和stateless两种类型的密钥管理方案的特点，配合自愈密钥发布方案，可以使组成员获得在由于无线信道的干扰而错过组密钥更新信息的情况下恢复出一定数量的组密钥的能力，提高了无线组播密钥管理方案的可靠性。更多还原

【Abstract】 With the development of internet and wireless cellular network, single voice service can not conform to the requirements of people any more. While the 3G communication system is getting into wide application, people do desire to enjoy services such as IPTV, games on line, which require high bandwidth, in wireless cellular networks. Large quantity, widely distributing of consumers, and messages received by users are the same characteristic of these services. Being much different from unicast and broadcast, multicast has the advantage of economizing bandwidth, easing network burden and decreasing congestion. At present, multicast security is an urgent problem, and the key point is the group key management. All members in a multicast group share only one group key. Messages should be encrypted by the key before they are multicasted. On receiving an encrypted message, group members can decrypt the message with the group key, while others can not Our goal is to find a way to distribute the new group key securely and efficiently. In this paper, after analyzing some related schemes about group key management, we propose a new key management scheme, which integrates the characteristics of both group key management schemes, stateful and stateless. Working with the scheme concerning self-healing group key distributing, group members can be able to recover some of the group keys when the rekeying message was missed because of some problems of the wireless channel. By this method, the reliability of schemes concerning group key management is improved.更多还原