【作者】 陈立山；

【导师】 谢敏；

【作者基本信息】 西安电子科技大学 ， 密码学， 2010， 硕士

【摘要】 不同于传统的多播路由算法,在多播通信网络中,网络编码的中间节点不仅仅是复制转发,而是把接收到的信息或数据进行编码等处理后再转发出去。因此,网络编码提高了网络的吞吐量,可使信息传输速率达到网络的最大流限。与此同时,随着对网络编码研究的不断深入,网络编码的安全问题也越来越重要。目前对网络编码的两类安全性威胁主要为窃听攻击和污染攻击。窃听攻击的安全性分为信息论安全的和弱安全的,区别是前者不允许得到信源的任何信息而后者则不允许得到信源的任何有意义的信息。污染攻击又分为传输节点的过滤污染攻击和信宿节点的过滤污染攻击。本文首先对网络编码的基本理论进行了全面系统的介绍;然后对线性网络编码理论进行了详细的阐述,介绍了线性网络编码的两种构造方式及各自的符号界。接下来对安全网络编码的两种攻击模型及其解决方法进行了介绍,并在窃听网络攻击模型下介绍了安全网络编码的一个必要条件;对防窃听和防污染的安全网络编码方法在随机数生成、种子发布和哈希函数计算三方面提出了自己的看法;对搭线窃听的线性网络编码的安全性进行了探索性研究,介绍了编码矩阵、编码策略及抗搭线窃听的线性网络编码的安全性度量的函数,给出了设计网络时需注意避免的编码向量的选取问题,最后对文献[49]的编码算法进行了适当改进,降低了编码复杂度,节省了存储空间。更多还原

【Abstract】 Other than traditional multicast routing algorithms, the intermediate nodes of network coding process the received information or data such as encoding and then forward it, not only duplicating and forwarding in multicast communication networks. Since the network information flow can approach the max-flow and the throughput is increased by adopting network coding. Simultaneously, the security of network coding is of importance as the research of network coding increases.At present the mainly security threats of network coding are the contamination and eavesdropping adversaries. The solutions of wiretapping attacks are categorized into two classes: information theoretically secure ones and weakly secure ones. The difference of these two classes is that the former does not allow the leakage of any information about the source while the latter disallows the leakage of any meaningful information. We classify the solutions against contamination adversaries into two classes depending on whether the pollution attacks are filtered by the forwarders or only the sinks.This paper first systematically introduces the basic theory of network coding. Then states a detailed explanation about linear network coding, introduces two construction ways and encoding symbol bounds respectively. Next presents the attack models and solutions of secure network coding, introduces a necessary condition in CSWN. We also propose our own thoughts in random number generating, seeds sending, hash computing on secure network coding against the contamination and eavesdropping adversaries. We introduce a exploratory study on the security of wire-tapping linear network coding. Also encoding matrix encoding strategy and the security function measurement of wire-tapping linear network coding are presented. The problem that choosing encoding vectors should avoid is given. At last we improve the encoding algorithm of paper [49], decrease the encoding complexity and save some memory space.更多还原