【作者】 王伟；

【导师】 诸昌钤；

【作者基本信息】 西南交通大学 ， 计算机应用技术， 2005， 硕士

【摘要】 组播技术提供了一种有效的通信、传输手段,它可以充分利用网络资源,优化网络性能,使那些用单播或广播不可行的新型增值应用成为可能。它在网络视频会议、网络音频/视频广播、股市行情发布、多媒体远程教育、大规模协同计算等诸多方面都有广泛的应用。本论文深入研究了距离矢量组播路由协议体系,在Net/3代码框架基础上实现了距离矢量组播路由协议的主要功能和协议的配置管理功能。本论文首先介绍了组播原理,然后分析了距离矢量组播路由协议原理及体系架构,详细介绍了协议报文处理流程和业务报文的转发流程。在协议的实现过程中,采用模块化设计方式,将程序分为四个模块:接口邻居模块、路由模块、嫁接和剪枝模块和定时器模块。接口邻居模块主要包含接口初始化与老化,本地组成员维护,通过接口发送和接收邻居探针报文;嫁接与剪枝模块包含剪枝状态信息的维护,剪枝嫁接报文的发送与接收处理,剪枝嫁接重传报文的发送与接收处理,与剪枝嫁接有关信息的老化;路由模块主要包含路由表的初始化,路由通告的发送与接收处理,路由表的老化等;定时器模块主要包括定时器队列的初始化,定时器的添加,定时器的删除,与定时器超时的相关函数的触发。同时,在协议的配置管理部分实现对协议的配置管理,显示协议运行状态信息和调试信息。更多还原

【Abstract】 IP Multicast provides an effective mechanism for communication and transmission. It can fully make use of the resource of the network, optimize the performance of the network and enable some distributed applications, which can’t be realized by unicast or broadcast. IP Multicast is broadly used in many areas such as teleconferencing, audio/video broadcast, stock market issue, distance education, computer supported cooperate work etc. In this thesis, the DVMRP (Distance Vector Multicast Routing Protocol) is studied thoroughly. The main function and the configuration management of the protocol are realized based on the Net/3. At the beginning of the thesis, the theory of the multicast is introduced, and then the theory of DVMRP protocol and the how to forward the packets are analyzed detailedly. The protocol is realized in four modules, interface and neighbor module, routing module, graft/prune module and timer module. The main function of the interface and neighbor module is to initialize and age the interface, maintain the local group members, send and receive probe packets. When it is come to the graft/prune module, it is to maintain the message of pruning state, send and receive graft/prune packets, age the message of pruning state. As to the routing module, it is to initialize and age the routing table, send and receive the routing packets. The last module is the timer module, which is to add a timer, delete a timer, and activate the functions when the time is up. At the same time, the configuration management of the protocol are realized to config the protocol, show the message of running and debugging.更多还原