分级Ad Hoc网络的组网研究

【作者】 张杨；

【导师】 余敬东；

【作者基本信息】 电子科技大学 ， 通信与信息系统， 2008， 硕士

【摘要】 移动Ad hoc网络(MANET)是一种不需要基础设施的多跳无线网络,它由多个无线节点组成,没有中心控制节点,是完全分布式的网络结构。网络节点可以随意移动,网络拓扑结构不断变化,组网灵活、方便、快速,有很强的抗毁性和抗干扰性,主要满足紧急、临时通信和军用移动通信的要求。Ad hoc网络按照节点间的组织关系可分为平面和分级两种结构:平面结构中节点之间为平等关系,网络健壮、安全性强,主要适用于中小型网络;分级结构的网络则由多个群组成,各群群首集中管理成员信息和提供群间路由,其良好的可扩展性非常适合大型网络。分级结构又可按照通信方式分为单频和多频分级两种。对于大型移动Ad hoc网络,需要高效的组网机制来实现控制开销少、可扩展性强的有机组织和运行。本论文通过对网络分级(分群)方式的选择、动态分群、IPv6地址自动配置、分级路由、移动性管理、群首数据库备份等问题的研究和分析,设计了一套以HOLSR(Hierarchical Optimum Link State Routing)路由协议为核心的多频分级Ad hoc网络优化组网方案。HOLSR协议是一种以平面OLSR为基础针对节点异构大型Ad hoc网络提出的分级路由协议,它充分考虑了异构网络的特点,在弥补了平面OLSR协议可扩展性不强这一缺陷的同时加入了分群和群成员信息交换机制。在HOLSR协议的基础上,本文的组网方案整合了动态分群和IPv6地址自动分配算法,设计了基于群成员信息交换的移动性管理算法,提出了群首数据库备份机制,目标是以尽量小的控制开销完成高效可靠、可扩展性和抗毁性强的多级网络自动组织及管理。仿真结果表明,该方案在大规模多频分级结构场景中能充分发挥网络中高性能节点的作用,提高组网过程的效率和性能,有效减小运行维护过程中的控制开销,保障了网络在移动过程中通信的快速、稳定和连续性,同时对网络的群移动方式提供了良好的支持。该方案为大型分级移动Ad hoc网络的组网实现提供了参考。更多还原

【Abstract】 Mobile Ad hoc NETwork (MANET) is a wireless multi-hop network without pre-established infrastructure. There is no central controller and MANET is completed distributed. Because of its convenience, quickness and robust, MANET can be used for emergency, temporary communication and military requirement.According to the structure MANET can be sorted into two categories: flat and hierarchical. Flat structure is mostly used in small and medium scale networks, where the nodes are completely equal to each other and the robusty is ensured. Hierarchical structure consists of clusters and is used in large scale networks for its high scalability. There are two communication methods in hierarchical networks: using single-frequency or multi-frequency. The large scale MANET needs self-organizing and working properly and efficiently under a series of protocols including clustering, routing, IP address assignment and mobility management, in which the routing protocol plays a key part because it determines the logical structure and communication performance of the network. Based on flat OLSR protocol, HOLSR (Hierarchical Optimum Link State Routing) is designed aiming to provide clustering, multi-level routing and members’management in hierarchical MANET.This paper proposes a build-up scheme for large scale heterogeneous MANET where a hierarchical architecture with multi-frequency is preferred. Optimized and combined operations of clustering, IPv6 address auto-configuration, HOLSR routing protocol and mobility management are proposed to reduce the control overhead and improve the scalability of the networks. And a mechanism of database backing up of cluster heads is designed to boost up the network’s robustness. Simulation results demonstrate that the scheme improves the efficiency and performance of the organization of heterogeneous ad hoc networks and supports nodes’group mobility well.更多还原