【作者】 邓世军；

【导师】 符云清；

【作者基本信息】 重庆大学 ， 计算机系统结构， 2008， 硕士

【摘要】 无线Mesh网络是由Ad Hoc网络发展而来的相对静态的无线网络,是Internet的无线版本。无线Mesh网络具有自组织、自配置和自治愈等特点,能够自动地将各个节点组织起来建立一个Ad Hoc网络并维持Mesh网络的连通性,具有有效的移动用户管理和跟踪机制,是一种多跳的宽带无线网络结构,也是一种高容量、高速率、低功耗、低成本的分布式网络。近几年来,无线Mesh网络技术取得了突飞猛进的发展,并获得了众多成功的商业应用。无线Mesh网络已经成为了下一代无线网络的关键技术。然而,无线Mesh网络仍然存在着诸如容量和范围增强、安全性、性能、功耗、带宽公平和多跳路由选择等问题,这些问题严重制约着无线Mesh网络的发展。由于无线Mesh网络还没有统一的标准,采用的路由技术主要是从Ad Hoc网络中移植过来的,并不能完全适合无线Mesh网络。本文在分析现有主流的各种无线Mesh网络路由协议的优缺点的基础上,根据无线Mesh网络的特点,提出一种适用于相对静态的无线Mesh网络的路由协议。本文开展的主要工作包括以下几个方面:①比较全面系统地总结了目前常见的各种无线Mesh网络路由协议,包括先验式路由协议,如DSDV、WRP、GSR协议等;反应式路由协议,如DSR、TORA协议等;混合式路由协议,如ZRP协议。②重点研究了Ad Hoc按需距离向量路由协议(AODV)的原理、实现过程。③在分析AODV路由协议的优缺点的基础上,提出了一种改进的、基于组合量度的路由协议(CMAODV)。不同于AODV协议的路由发现采用最短跳数量度,CMAODV协议使用了节点缓存饱和度、可用带宽、跳数三种量度组成的综合选路尺度。该协议的核心思想是尽量避开负载较重的节点,选择从源节点到目的节点负载较轻的路径,从而减少网络拥塞,均衡网络流量。同时CMAODV协议增加了重负载节点拒绝路由请求转发,减少了路由请求广播的开销。④对CMAODV协议的性能进行仿真分析,并与AODV协议进行对比。实验结果表明,本文提出的CMAODV协议在无线Mesh网络环境下要优于经典的AODV路由协议。更多还原

【Abstract】 Wireless Mesh, evolving from Ad Hoc network, is wireless version of Internet with comparative static characteristics. Featuring self-organization, self-configuration and self-healing, wireless Mesh is able to automatically organize each node into an Ad Hoc network and maintain its connectivity. It obsesses effective management and tracing mechanism of mobile users and has a broadband wireless network structure featuring multiple hops. Wireless Mesh is distributive network characterizing high capacity, high speed, low power consumption and low cost.In recent years, wireless Mesh technology has scored big points rapidly and is widely used in commercial sectors, being key part of technology in next generation wireless network. Despite of above mentioned merits, problems such as capacity and coverage enhancement, security, performance, power consumption, bandwidth fairness and multiple host choice, etc still exist which constrict its further development. Routing technologies being adopted is transplanted from Ad Hoc network due to lack of standard, therefore they don’t fit wireless Mesh network well.After analysis on strength and weakness of existing routing protocols, this thesis presents a routing protocol with comparatively static property in line with wireless Mesh network’s characteristics. We focus effort on routing technologies of wireless Mesh network which are as follows:①Research on common routing protocols of Mesh network, including proactive ones such as DSDV, WRP, GSR, etc; reactive ones: DSR, TORA, etc; hybrid routing protocols: ZRP.②Focus on the study of principles and implementation process of Ad-hoc On-demand Distance Vector Routing Protocol (AODV).③An improved Ad hoc On-demand Distance Vector based on Combined Metric routing protocol (CMAODV) is proposed through analysis on merits and weakness of ADOV. Instead of minimum hop count, we propose a combined metric substantially consist of node’s load, available bandwidth and hops. Its main idea is that avoiding the node of heavy load, inducing the network’s congestion, balancing network’s flow. CMAODV add that the node of heavy load refuse route’s forward, so induce route costs.④Conduct simulation and analysis against performance of CMAODV and compare with AODV. Results of simulation show that in wireless Mesh network, CMAODV is better than traditional AODV.更多还原