基于WMPLS的无线自组网组播路由机制

将多协议标签交换(MPLS)技术与无线自组网组播机制相结合可以把MPLS在分组转发以及支持服务质量、流量工程等方面的技术优势引入到无线自组网组播路由协议设计中,具此提出了一种基于MPLS技术的组播协议设计方案——标签交换转发组播协议(Label-Switching Forwarding multicast routing protocol,以下简称LSF组播协议)。     

移动Ad Hoc网络中一种多播路由协议算法实现

MANET是一个多跳,节点无中心、自组织、互相通信而不依赖于预先架设的固定基础设施无线移动网络。本文提出了采用按需路由发现策略的移动Ad Hoc多播路由算法。此算法不需要维护全局的路由信息,通过按需路由发现过程,动态更新路由信息和建立多播转发组。多播数据包在转发组成员间进行有限泛洪,能够降低带宽的占用及减少路由更新信息的传播。仿真实验显示多播算法在带宽较低、多播组成员数量变化较大的移动分组无线网环境中,具有较好的可靠性和工作效率。     

E-ODMRP: Enhanced ODMRP with motion adaptive refresh

On-Demand Multicast Routing Protocol (ODMRP) is a multicast routing protocol for mobile ad hoc networks. Its efficiency, simplicity, and robustness to mobility render it one of the most widely used MANET multicast protocols. At the heart of the ODMRP’s robustness is the periodic route refreshing. ODMRP rebuilds the data forwarding “mesh” on a fixed interval and thus the route refresh interval is a key parameter that has critical impact on the network performance. If the route refresh rate is too high, the network will undergo too much routing overhead, wasting valuable resources. If it is too low, ODMRP cannot keep up with network dynamics, resulting in packet losses due to route breakages. In this paper, we present an enhancement of ODMRP with the refresh rate dynamically adapted to the environment. Simulation results show that the Enhanced ODMRP (E-ODMRP) reduces the packet overhead by up to a half yet keeping a packet delivery ratio comparable to that of the original ODMRP. E-ODMRP compares favorably with other published multicast schemes.     

Performance evaluation of a mesh-evolving quality-of-service-aware multicast routing protocol for mobile ad hoc networks

The tremendous amount of multimedia applications running across the wireless communication medium makes quality of service (QoS) a fundamental requirement for mobile ad hoc networks. However, it is not easy to incorporate QoS into these networks. Moreover, the growing number of group-oriented applications also necessitates the efficient utilisation of network resources. The multicast model is a promising technique which can achieve this efficiency by facilitating the inherent broadcast capability of the wireless medium. The mesh-evolving ad hoc QoS multicast (MAQM) routing protocol is developed to address the resource efficiency and QoS problems with one, integrated solution. MAQM achieves multicast efficiency by tracking the availability of resources for each node within its neighbourhood. The QoS status is monitored continuously and announced periodically to the extent of QoS provision. Using these features, MAQM nodes can make their decisions on joining a new multicast session based on the sustainability of their perceived QoS. MAQM also evolves the initial multicast tree into a mesh during the course of an ongoing session to achieve a more robust network topology. Thus, MAQM integrates the concept of QoS-awareness into multicast routing in mobile ad hoc networks. Since ad hoc networks require the protocol control overhead to be as small as possible, we analyse the multicast session establishment process of MAQM to see its impact on the protocol performance in terms of system control overhead. We also evaluate the performance of MAQM through computer simulations using various qualitative and quantitative criteria. The simulation results validate our mathematical analysis of the control overhead and show that MAQM significantly improves multicast efficiency through its QoS-aware admission and routing decisions with an acceptably small overhead. Thus, MAQM shows that QoS is not only essential for, but also applicable to mobile ad hoc networks.     

一种基于稳定簇的混合路由协议CBHRP

移动算组网是一种没有有线基础结构支持的移动网络,具有带宽有限和拓扑结构易变的特点。这些特点使得设计一个合适的路由协议具有一定的挑战性。该文针对移动自组网提出了一种基于稳定簇结构、按需路由和预先路由混合、支持单播和组播通信的路由协议CBHRP。CBHRP具有路由控制开销小、主机移动对拓扑结构改变的影响小、通信的初始延迟低和应用范围广的特点。     

可变核心的Ad hoc组播路由协议

针对Ad hoc网络中信源节点增加时ODMRP按需组播路由协议会产生大量的控制开销,提出了一种优化的基于可变核心算法的组播路由协议VCMP(variable core multicast route protocol).该协议的核心不必事先固定,而是能根据当前的网络拓扑和组成员关系进行变化,利用核心的帮助,能解决ODMRP环境中所会出现的控制开销问题,使整个网络中的控制包大大的减少.仿真结果表明VCMP确实有更好的性能.     

一种基于MANET的多播协议的设计与实现

传统的应用于有线网络的多播方法很难适应MANET所具有的拓扑结构变化和带宽有限等特点，无法有效地应用于MANET。提出了采用按需路由发现策略的MANET多播路由协议MFGRP。在MFGRP协议中不需要维护全局的路由信息，通过按需路由发现过程，动态更新路由信息和建立网格。多播数据包在转发组成员间进行有限泛洪，使协议能够降低带宽的占用及减少路由更新信息的传播。模拟实验显示协议在带宽较低、多播组成员数量变化较大的移动分组无线网环境中，具有较好的可靠性和工作效率。     

一种改进的链路独立的MANET网络路由协议

MANET网络具有高速移动以及频繁的链路失败等特点,这将导致吞吐率降低以及很高的端到端时延.为减少由于此类原因的路由发现次数以及开销,我们使用多径路由来提供备选路径.论文提出一种基于AOMDV的改进链路独立多径路由协议.通过仿真表明改进后的LD-AOMDV在节点移动速度较高时数据包投递率、端到端平均时延、归一化路由开销等方面都明显优于AOMDV.     

Applying link stability estimation mechanism to multicast routing in MANETs

Mobile ad hoc networks are self-organizing network architectures of mobile nodes. Node mobility causes network topologies to change dynamically over time, which complicated important tasks such as routing. In this paper, a novel link stability estimation model based on received signal strength indication is proposed. We have integrated this model into MAODV and present a stability-based multicast routing protocol termed as SMR. SMR can discover more available stable routes and better adapt to network topology changes. Simulation results show the superiority of SMR over the existing methods in terms of packet delivery ratio, average end-to-end delay and routing packet overhead.     

基于群组移动模型的OLSR协议性能仿真与评估

在研究移动自组网移动模型和无线路由协议的基础上,选取移动自组网中具有代表性的参考点群移动模型,基于ns2网络模拟平台,以参考点群组移动模型生成移动场景文件,应用层使用cbr数据流量,对OLSR无线路由协议在不同参数条件下的性能进行了模拟测试。通过对测试结果数据的详细分析,总结得出了OLSR无线路由协议在参考点群移动模型下端到端时延、报文交付率和路由负载三个方面的特点。为进一步研究移动自组网下基于OLSR协议的各种应用提供参考。     

Ad Hoc网络多路径需求路由及路径熵选择算法

无线移动Ad Hoc网络是一种不依赖任何固定基础设施的移动无线多跳网络.由于其动态性和资源的限制,在Ad Hoc网络中提供多路径路由是一个重要的研究课题.描述了一种Ad Hoc网络中基于信息熵选择的稳定多路径路由算法(stability multipath on-demand routing,简称SMDR),提出了路径熵的度量参数,并利用路径熵来选择稳定的、长寿命的多路径,减少了重构路由的次数,从而在网络拓扑频繁变化的Ad Hoc网络环境中较好地提供QoS保证和提高数据传输率.仿真结果表明,SMDR协议改进了分组传输率、端到端时延和路由负载率.SMDR协议为解决动态的Ad Hoc网络多路径传输提供了一种新的有效途径.     

动态源路由协议(DSR)在Linux下的实现

动态源路由协议(DynamicSourceRoutingProtocol,DSR)是由移动节点组成的多跳无线AdHoc网络犤3,4犦中一种简单和行之有效的路由协议犤1犦。协议允许任一结点动态发现到达AdHoc网络中其它任意节点的路由,所有的路由信息由DSR自动地进行维护。每个DSR头部都携带了到达目的节点的完整的路由跃点列表(hoplist),中间节点只需简单地对分组进行转发即可。同时DSR协议完全按需(on-demand)的特性可以显著减少路由协议的开销,节省了电池能量,减少了分组冲突的概率并减少了潜在的大规模的路径更新信息的传播。使用DSR协议可以实现AdHoc网络的完全的自组织和自配置而无需任何已经存在的网络基础设施。论文详细论述了DSR路由协议在Linux操作系统下借助Netfilter的实现。     

基于本地信任系统的可靠动态源路由协议

移动Ad hoc 网自组织、移动性等特性为组网带来便利的同时也增加了路由管理的难度.针对现有可靠路由算法解决问题具有局限性以及获取链路评价信息低效等问题,在DSR(dynamic source routing)协议基础上提出了基于本地信任系统的可靠路由协议(reliable routing protocol based on local trust system,简称TR-DSR).TR-DSR 协议选择路由时,综合考虑路由上各节点和各链路的可靠信任度,并在路由建立过程中利用这些信息,在确保找到可靠路由的基础上降低寻路开销.同时,为了防止自私节点对信任系统评价正确性的影响,提出了基于GTFT(generous tit fortat)策略的激励节点推荐响应行为的DFR(decide forwarding recommendation)算法.仿真实验结果表明,在节点频繁移动和存在大量自私节点的网络中,该协议的性能优势明显,验证了TR-DSR 协议的可靠性.     

基于按需路由的MPRN路由协议

提出了采用按需路由发现策略的MPRN路由协议OFGRP。在OFGRP协议中不需要维护全局的路由信息，通过按需路由发现过程，动态更新路由信息和建立网络。数据包在转发组成员间进行有限泛洪，使协议能够降低带宽的占用及减少路由更新信息的传播。模拟实验显示协议在带宽较低的MPRN网络环境中，具有较好的可靠性和工作效率。     

两种Ad hoc网络组播路由协议的性能比较和分析

目前研究人员已提出多种Adhoc网络组播路由协议,根据MANET制定的路由协议性能评价标准,还没有一种组播路由协议能满足所有的性能要求,因此对协议在各种应用环境下的性能进行测试和比较,有助于人们选择和设计组播路由协议。该文首先介绍了两种组播路由协议—ODMRP和DBRMP的基本思想,接着提出这两种协议的控制开销计算方法,并对它们的性能进行了定性比较,最后使用了NS-2仿真平台对两种组播路由协议在各种应用环境下的性能进行了仿真,并根据仿真结果详细比较和分析了两种协议在各种应用环境下的性能特点。     

An ad hoc multicast protocol based on passive data acknowledgement

An ad hoc network is a multi-hop wireless network of mobile nodes without fixed infrastructure. Its limited bandwidth and frequently changing topology require that its protocol should be robust, simple and energy conserving. In this paper, we propose a new ad hoc multicast protocol based on Passive Data Acknowledgement (PDAODMRP). PDAODMRP has the following contributions: (1) it knows the status of its downstream forwarding nodes by route information collected from data packets instead of BEACON signal of MAC layer, and reduces the waste of wireless bandwidth created by the BEACON signal; (2) it adopts a new route information collection from data packets to reduce the CPU usage of data route information collection; and (3) it adopts a dynamic local route maintenance to enforce its local route maintenance. From simulation results, it can be seen that PDAODMRP has low control overhead and low data delivery delay.     

移动自组网路由局部修复算法的研究

移动自组织网(mobile ad hoc networks,MANET)的多跳的无线连接、动态拓扑和有限的带宽等特征,给其路由协议带来了很多挑战.当多跳路径失效时,路由协议需要对其进行修复.已有的修复机制需要很多的开销和很长的端到端时延.在此修复机制的基础上,提出了一种新的路由局部修复算法,将修复尽量限制在断链的局部范围内,以减少对链路断裂的反应时间和降低路由维护的开销,而且不用考虑失效链路在整个路由上的相对位置,都可以对其进行修复,提高了处理失效链路的能力,有利于提高MANET的可扩展性.仿真表明,这种新的路由局部修复算法明显地提高了网络多方面的性能.     

一种稳定的按需QoS路由协议

一个ad hoc网络是一个多跳无线网络,网络中的节点互相通信而不依赖于预先架设的固定基础设施，选路协议中的频繁的路由失败和高控制开销致使系统性能降低.本文提出了一个稳定的分布式Ad hoc路由协议，该协议支持QoS选路用于多媒体应用．     

车载自组网路由稳定性分析

针对车载移动ad hoc网络的特点,从路由断裂的角度在原理和理论上分析了车载移动ad hoc网络路由不稳定的各种情况,在分析结论的基础上提出了一种不依赖GPS信息的基于节点相对稳定性的类AODV路由协议RSBA（Relative Stability Based AODV Routing Protocol）,通过可行性分析及实验仿真证明了新协议比AODV协议更适合节点密度较高的城市车载环境,具有较低的路由断链率和路由负载,有效降低丢包率,可扩展性提高,同时验证了对车载移动ad hoc网络路由稳定性分析策略和结论的正确性。