具有用户匿名性的组密钥分发协议的设计与实现

发布时间：2018-09-19 13:18

【摘要】：组播是一种区别于单播的通信技术,它采用“一对多”的通信方式,现实生活中,许多新型应用如视频点播、远程教学和网络会议等都使用了组播通信技术。组播通信技术的日益发展,就使得组播的安全性问题显得更加突出,其中组播密钥管理就是其中需要重点关注的问题之一。但是,目前针对组播密钥管理方案的研究主要集中在如何降低密钥存储量和提高加密及解密的效率问题上,而忽略了组播通信技术中的固有属性。确切地说,这些研究的重点为组播组中的发送方提供了必要的安全需求,却忽视了组播组中接收人员的隐私问题。经典LKH协议实现中,动态变化成员的身份信息是直接以明文形式存在于密钥更新信息中的,假设窃听者获取到该密钥更新信息,虽然他不能够获取到任何有效的数据,但是却可以轻而易举地获取到成员身份信息。这就会导致成员隐私泄露。本文就当前已有的解决方案进行研究,特别是LKH协议,并且分析它的优缺点。然后针对成员隐私泄露的问题,在LKH协议上进行相关改进。设计一种具有用户匿名性的组密钥分发协议。首先,在LKH协议的实现中,设计一种提高组播组中成员解密效率的编号形式。这种编号形式借鉴了类似哈夫曼编码的思想,为密钥二叉树中的每个树节点进行编号,这样就可以提高密钥更新时的效率。其次,针对成员隐私泄露问题,设计索引匹配算法,该算法中通过伪随机函数的计算,将经典LKH协议中明文出现的成员身份信息进行“隐藏”,是改进后的协议具有用户匿名性,避免成员隐私外泄的问题发生。最后,将改进的协议进行实现,并且分析其相关计算开销和存储开销等问题,验证其可行性。通过这些使该改进后的协议能够满足实际生活中的应用,利于组播通信技术的推广使用。
[Abstract]:Multicast is a kind of communication technology which is different from unicast. It adopts "one-to-many" communication mode. In real life, many new applications such as VOD, distance learning and network conference use multicast communication technology. With the development of multicast communication technology, the security of multicast becomes more and more prominent, among which the key management of multicast is one of the most important issues. However, the current research on multicast key management mainly focuses on how to reduce the amount of key storage and improve the efficiency of encryption and decryption, while ignoring the inherent attributes of multicast communication technology. To be exact, these researches focus on providing the necessary security requirements for the sender in the multicast group, but ignoring the privacy of the receiver in the multicast group. In the classical LKH protocol implementation, the identity information of the dynamic member exists directly in the key update information in clear text. Suppose the eavesdropper gets the key update information, although he cannot obtain any valid data, However, membership information can be easily obtained. This can lead to member privacy disclosure. This paper studies the existing solutions, especially the LKH protocol, and analyzes its advantages and disadvantages. Then the LKH protocol is improved to solve the problem of member privacy disclosure. A group key distribution protocol with user anonymity is designed. Firstly, in the implementation of LKH protocol, a numbering scheme is designed to improve the decryption efficiency of multicast group members. This numbering form draws lessons from the idea of Huffman coding and numbers every tree node in the key binary tree so as to improve the efficiency of key updating. Secondly, aiming at the problem of member privacy disclosure, an index matching algorithm is designed. In this algorithm, the membership information in the classical LKH protocol is "hidden" by the calculation of pseudorandom function. The improved protocol has user anonymity and avoids the problem of member privacy leakage. Finally, the improved protocol is implemented, and its computational overhead and storage overhead are analyzed to verify its feasibility. Through these, the improved protocol can meet the practical application, which is conducive to the popularization and use of multicast communication technology.
【学位授予单位】：云南大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TN918.4
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本文编号：2250242