【作者】 陈亮；

【导师】 张宇；

【作者基本信息】 华南理工大学 ， 计算机应用技术， 2012， 硕士

【摘要】 随着近年来的互联网发展，IP地址不断地消耗，IP地址短缺的问题却始终难以得到解决，因此，NAT技术部署越来越广泛。根据RFC定义，网络地址翻译器(NAT)是一种将IP地址从一个编址域(realm)映射到另外一个编址域的方法[1]。不过，NAT技术的应用也给网络拓扑带来更多的复杂性，增加了互联网应用的部署难度。其中多媒体业务穿透NAT就是难点之一。这几年，网络流媒体应用越来越广泛，许多创新型的应用都是基于互联网的多媒体业务，而这也正是下一代互联网发展趋势——更大数据量更高速的进行传输。而NAT穿透功能则是这些多媒体应用所不可缺少的，目前国内外在流媒体穿透NAT的研究领域上，存在许多不同的技术，并没有统一的标准，各种技术都存在优点和缺点。本文主要研究内容是基于其中一种NAT穿透方法——ICE协议，通过改进ICE协议，实现了流媒体穿透NAT的技术方案。在文中的原理理论论述中，概述了NAT问题的发展起源以及NAT相关的类型，同时，针对国内外对NAT穿透问题的研究现状进行了分析，综合比较了它们各自的优势与劣势。在这些研究的基础上，着重对ICE协议进行了研究，并提出了改进的算法与架构设计，引进了分布式与P2P的理论研究，同时基于改进的ICE协议进行了穿透NAT系统的设计与实现。通过采用软件工程的理论，对系统各个模块进行分析设计，并进行了相关测试，利用测试结果来验证理论，表明本文研究的解决方案可以很好地应用与实际项目中。更多还原

【Abstract】 As Internet developing in recent years, the problem of the shortage of IP address isdifficult to solve all the time, so the NAT technology deploys more and more commonly.According to RFC, the address translater of network (NAT) is one method that translates IPaddress from one realm to another one. However, NAT technology brings more complexity tothe network topology, which increases the difficulty of employing the Internet application.Among them it is one of the difficult points that the multimedia business traversing NAT.During these years, the application of the streaming media of the network is more andmore extensive, a lot of innovative application is based on the Internet multimedia bussiness,and this one is exactly the development trend of next generation of Internet, which is morehigh-speed transmitting of the bigger data. Traversal NAT is indispensable one function ofthese multimedia applications. Now, there are a lot of different technologies in the research oftraversal NAT at home and abroad, and there is no unified standard, and various technologiesalso has advantages and disadvantages. In this paper, the main research is the ICE protocolbased on one of the methods of traversal NAT, and through improving ICE protocol, how torealize the technological scheme of the streaming media traversing NAT.The principle theory in the paper describes the development origin of NAT problem andNAT relevant types, at the same time, analyze the current research of NAT problem at homeand abroad, compared the advantages and disadvantages synthetically. On the basis of thesearchivements, I carry on the researches of the ICE protocol, and propose the improvingalgorithm and design the framework, introducing the theoretical research of distributed andP2P. And then I design and realize the system based on the new theory. By using the theory ofsoftware engineering, I design each module of the system and carry on the relevant test, andmake use of the test results to verify the algorithm and theory, so that the solution can be wellemployed in the actual projects.更多还原