Ad-hoc网络多径路由协议的研究与设计

对目前典型的Ad-hoc网络按需多径距离矢量路由协议(AOMDV)进行了研究和优化设计.优化后的协议(Op-AOMDV)保留了原协议中建立多径无环路由的思想,改进了原协议中建立链路不相交路由等不完善的部分,给出了原协议中未提及的细节,降低了协议的复杂性,提高了协议的可实现性.     

基于AODV的延长网络生存时间的路由协议

在AODV基础上优化了路由发现过程,提出了延长网络生存时间的路由协议(LL-AODV)。该协议在路由发现时考虑了链路可用时间的约束和节点的能量,并且通过网络模拟器(NS-2)对相同场景下AODV与LL-AODV路由协议进行了模拟。仿真结果表明新的路由协议在延长网络生存时间方面有明显改善。     

On supporting high-throughput routing metrics in on-demand routing protocols for multi-hop wireless networks

Researchers have proposed routing metrics other than hop count, such as ETX (expected transmission count) and ETT (expected transmission time), to find routes with high throughput. These metrics are inherently suitable to be used in source routing protocols such as DSR, because link state information needs to be collected for the calculation of the shortest path. In this paper, we propose an efficient and generalized approach called accumulated path metric (APM) for supporting high-throughput metrics (HTMs) in on-demand routing protocols. One advantage of APM is that it is able to find the shortest path, in terms of a particular metric, without collecting topology information and without running a shortest-path algorithm. This will significantly simplify the existing design of supporting HTMs in DSR. We present a proof of the correctness of APM. Moreover, we address the problem of duplicate RREQ (route request) transmissions with existing HTM schemes and present a broadcast ordering (BO) technique to suppress unnecessary RREQ transmissions. We study the performance of APM and BO in both AODV and DSR, and the results verify the effectiveness of the proposed approaches.     

移动AODV协议的优化设计与仿真测试

AODV采用按需的方式建立路由,从而相对其他MANET路由协议来说在能耗和开销方面都有较大的改善.但该协议在寻径过程中仅凭序列号来决定最佳路由,当序列号相同时则采用跳数最小的方式来确定最佳路由.无形中会使得某些次优路由被丢弃,从而增加了数据传输的时延.针对这一问题,提出来一个改进方法,在改进的协议中,源节点在序列号相同的情况下,同时保留最佳路由和次优路由以备不时之需.仿真结果表明改进的协议和原协议相比,降低了端到端的延时,更适合实时性要求高的应用.     

一种基于AODV改进的城市车载自组网路由协议研究

针对城市环境下车载自组网的特点及AODV协议广播式路由探测的不足,采用贪婪转发的单播式路由探测和经典AODV协议的广播式路由探测相结合的路由探测方式,并且单播路由探测在选择下一跳转发节点时同时考虑贪婪转发和链路稳定两个因素,减少了广播帧的发送,提高了路由的稳定性。仿真实验表明,改进后AODV协议比经典AODV协议更加适合城市车载自组网。     

Ad Hoc路由协议实现技术

针对目前的Ad-Hoc网络的研究大多在模拟环境进行的现状,对AODV路由协议实现展开了研究,提出了一种在Linux系统中基于Netfilter功能框架的AODV协议设计与实现方法.搭建了以PXA310处理器和IEEE802.llb无线网卡为核心的硬件平台,完成了基于Netflter功能框架的AODV路由协议的软件框架,...     

AODV routing overhead analysis based on link failure probability in MANET

This article puts forward an Ad-hoc on-demand distance vector routing(AODV)routing overhead analysis method in mobile Ad-hoc network(MANET).Although multiple routing protocols have been proposed to improve the performance,scarcely any paper analyzed the routing overhead caused by routing setup and maintenance processes in mathematical way.Routing overhead consumes part of network resources and limits the supported traffic in the network.For on-demand routing protocols like AODV,the routing overhead depends on the link failure probability to a great extent.This article analyzes the collision probability caused by hidden-node problem and the impact on link failure probability.In chain and rectangle scenarios,it presents a mathematical analysis of the theoretical routing overhead of AODV protocol based on link failure probability.Simulations on OPNET 14.5platform match well with the theoretical derivation which confirms the effectiveness of the analysis method.     

一种改进的基于AODV的分簇路由协议

基于距离向量的按需路由协议AODV是移动Ad Hoc网络研究的热点之一.文中提出一种基于AODV的分簇路由协议CAODV,该协议通过增加分簇机制,将AODV协议改进为层次型的路由协议.与AODV协议仿真比较后可以看出,改进后的CAODV协议在分组转发率和路由开销方面的性能有较大提高.     

一种基于节点移动性的AODV改进协议

移动Ad hoc网络是移动节点动态临时组建的自组织网络,路由协议一直是Ad hoc网络研究的关键问题.文中提出了一种新的AODV改进协议AODV-NM,它能够根据节点速度自适应的调整RREQ泛洪频率,实现稳定路径的选取.仿真结果表明,AODV-NM能够有效降低网络路由负荷,同时改善了时延与分组投递率等性能.     

路由信息的攻击对AODV协议性能的影响分析

AODV协议是移动自组网络中一种按需反应的表驱动路由协议。在移动自组网中，每个节点既是计算机又是路由器，容易遭受基于路由信息的网络攻击，而现今的路由协议基本没有考虑到该问题。本文在分析移动自组网中针对路由信息主要攻击方法的基础上，建立了主动性和自私性两个攻击模型，并且在AODV协议中扩充实现了这两类攻击行为。通过对模拟结果的分析和比较，讨论了路由信息的攻击对AODV协议性能的影响，并进一步探讨了针对基于路由信息攻击的防御措施。