【作者】 汤剑君；

【导师】 王林平；

【作者基本信息】 华中师范大学 ， 计算机应用， 2006， 硕士

【摘要】 VoIP是以IP分组交换网络为传输平台,对模拟语音信号进行压缩、封装等一系列的处理,使之可以采用TCP或UDP协议进行传输,从而达到语音通话的目的。作为在IP网络上提供实时语音传输的方案,VoIP以其多元化的服务和低廉的价格迅速发展起来。随着因特网的日渐成熟,VoIP的广泛应用势必会加快电信网络和IP网络的融合。 然而现有的VoIP应用大多是基于C/S模型的,资源有限必然成为阻碍VoIP发展的主要因素。P2P系统因其各节点完全对等和网络自组织性等原因而天生具有高可伸缩性和高可靠性等特点。在VoIP中引入P2P技术,可以有效缓解资源有限的难题,改善网络的可伸缩性和可靠性。 本文即是在VoIP与P2P结合方面做出了有益的尝试,提出了VoIP中基于Chord的P2P模型,并进行了详细的研究。 本文首先分析了VoIP应用及其关键技术,包括VoIP原理和相关协议等。接着研究了P2P模型及其关键技术,包括P2P模型的分类、基于Chord的分布式查找系统、NAT及防火墙穿越和Skype工作原理分析等。在此基础之上,提出了VoIP中基于Chord的P2P模型,详细论述了模型中节点的操作,并对其性能进行了分析。最后对全文进行了总结及对未来工作进行了展望。更多还原

【Abstract】 VoIP is a term used in the IP network for a set of facilities for managing the delivery of voice information using the TCP/UDP. As a solution of real time voice delivery in the IP network, VoIP has been developing rapidly because of it’s lower cost and higher efficiency compared with traditional telephony. With the development of the Internet, VoIP application certainly will speed up the combination of telecommunication network and IP network.However, most of today’s VoIP applications are based on Client-Server model. The limitation of resources will restrict the development of VoIP. P2P systems inherently have high scalability and reliability because there is no centralized server and the network self-organizes itself. If we introduce P2P technologies in VoIP, the capability will be improved greatly.Our work is an attempt of combination of P2P and VoIP. We propose a pure P2P model based on Chord for VoIP.This thesis firstly analyses the VoIP application and the P2P model and related key technologies. Secondly it does research on the scalable lookup based on Chord and analyses the Skype application. Thirdly, it proposes a P2P model based on Chord for VoIP, and describes the operation of node in the model entirely. Finally, it gives the summarization and the future work.更多还原