【作者】 崔伟峰；

【导师】 金顺福；

【作者基本信息】 燕山大学 ， 计算机应用技术， 2007， 硕士

【摘要】 Ad hoc网络(也称移动自组网)是一种特殊的,不依赖于任何固定通信设施的无线网络。Ad hoc网络的特点使得其路由选择机制与其他网络相比更加复杂。传统的因特网组播协议不能适应Ad hoc网络拓扑结构快速变化的需要,因此对Ad hoc网络设计切合其自身特点的新的组播路由协议成为研究热点。本文分析总结了多种Ad hoc组播路由协议,并深入研究了其中比较先进的ABBM(Adaptive Backbone-based Multicast routing protocol)协议。通过分析其路由机制,找出了ABBM协议在协议的扩展性、分级的合理性和避免主干网络上的节点成为传输瓶颈等方面存在的缺点。针对这些缺点设计出了一种新的ABBM协议,即E-ABBM协议。首先,对ABBM协议所采用的WCA(Weighted Clustering Algorithm)分簇算法进行改进。为了提高簇的稳定性,将原分簇算法中的一个权值参数即节点平均速度改为节点间的平均相对速度,提出了新的分簇算法EWCA。其次,引入了混合路由发现策略,即在簇内采用预选式路由发现策略,在簇间采用随选式路由发现策略。最后,利用网络仿真软件NS(Network Simulation),建立相关的仿真模型,并进行了仿真实验,通过实验验证E-ABBM协议在分组投递率、网络传输延迟和网络扩展性等方面的先进性。更多还原

【Abstract】 Ad hoc network is a kind of special wireless network in which no base stations are supported, consisting of a set of mobile hosts that play the role of both host and router, may communicate with one another through multi-hop and roam around at their will. In a word, the specialty of the Ad hoc network makes its routing more complex than other networks. Traditional internet multicast routing protocols can’t meet the quickly-changing of the network topology, so designing the new multicast routing protocols which are suitable for Ad hoc network is hotspot.The paper sorts the existing multicast routing protocols in Ad hoc network into different types, and compares, analyzes, illuminates the content of different types of protocols, especially analyses ABBM (Adaptive Backbone-based Multicast routing protocol), which is advanced than the other. By analyze routing mechanism in ABBM, discovered that it has limitations in the scalability of multicast protocol and cluster stability. Then design the enhance scheme of ABBM: E-ABBM.Firstly, scheme of WCA (Weighted Clustering Algorithm) in ABBM is improved. Modify the average speed of node which is the weight-parameter of WCA to the average relatively speed among nodes for improving the stability of cluster, design the new clustering algorithm for the large scale Ad hoc networks router.Secondly, import the hybrid of reactive and proactive routing scheme. Use proactive routing scheme within cluster and reactive routing scheme among clusters.Finally, the different protocols including E-ABBM and ABBM are simu- lated on platform of the NS (Network Simulation). By the results of simulation,concluded that E-ABBM has better performance as packet delivery ratio and network delay and expansibility.更多还原