Ad Hoc网络中的多播路由协议

无线Ad Hoc网络是指一组无线移动节点组成的多跳的,临时性的,无基础设施支持的无中心网络。多播是一种面向群组计算的通信传播方式,它使用单一的源地址把数据发给一组主机。如何在移动自组网中实现有效的多播路由技术是当前此领域研究中亟待解决的问题。文中对当前一些典型的多播路由协议进行了研究,并对它们各自的工作方式进行了分析,最后对它们各自的特点进行了比较。     

AdHoc网络多播路由协议研究进展分析

基于AdHoc网络的特殊性,固定网络中已有的多播路由协议已经难以有较好的适应度,怎样在移动无线自组织网络中实现效率较高的多播路由已成为一个极具挑战性的问题。分析了移动无线自组织网络中多播路由协议所具有的问题以及相应的设计要求;详细阐述了现有的移动无线自组织网络多播路由协议,并对该网络中不同多播路由的方法进行了分析和比较;对移动无线自组织网络中的多播路由协议的使用进行了总结。     

基于Ad Hoc的QoS多播路由协议研究

近年来,随着计算机网络和无线通信技术的迅速发展,无线移动AdHoc网络在军事和民用方面获得了大量应用。多媒体业务的引入对AdHoc网络提出了多播和QoS服务的需求,如何在AdHoc网络中实现有效的多播和QoS服务是一项十分困难和具有挑战性的工作。论文介绍了当前几种比较典型的QoS多播路由协议,并且从多个方面对它们的特性进行了比较分析,最后对AdHoc网络的QoS多播路由协议的进一步研究提出了预测和展望。     

移动Ad Hoc网络多播路由协议的研究进展

移动AdHoc网络是一个自组织、移动节点通过无线链路组成的动态拓扑变化的网络.由于网络规模小、无基础设施、构建迅速等特点,从而广泛用于紧急事件、军事和民用领域以及多媒体应用等.随着网络应用规模的增长,在移动AdHoc网络中支持多播路由成为网络领域中一类重要的研究课题.该文综述了移动AdHoc网络多播路由方面的一些最新工作,论述了设计移动AdHoc网络多播路由协议的特性、问题和技术,详细描述和比较了目前典型的移动AdHoc网络多播路由协议,为进一步的应用和研究提出了新的课题.     

移动自组网上基于动态蜂窝的多播路由协议

移动自组网是一种新型的无基站无线移动网络,多播作为通信网络中的重要功能,在这种网络中具有很高的研究及使用价值.针对移动自组网的特性,提出了基于动态蜂窝的多播路由协议.该协议将移动结点组织成动态蜂窝,然后在此基础上以按需的方式建立网格结构的多播路由发送多播数据.仿真实验结果表明该协议具有延迟小、可靠、高效、扩展性强的特点.     

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。     

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AdHoc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。     

基于MAODV多播路由协议的改进协议

MANET(移动自主网)是由一组带有无线收发装置的移动终端组成的一个多跳的临时性自治系统,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,在军用和紧急救援等特殊环境的应用前景非常广阔。多播是有利于成员组通信的方式,高效的多播路由是MANET网络多播路由的主要难题。文章在MAODV的基础上,提出了基于GroupH ello(GRPH)消息机制、路由发现和路由维护的MAODV多播路由协议的改进协议,仿真实验显示改进后的协议减少了开销、降低了时延,在高动态的网络中尤为明显。     

一种改进的基于移动预测的可扩展多播路由协议

移动Ad Hoc网络是由一组带有无线收发装置的移动节点组成的一个支持多跳的临时性的网络自治系统,随着网络应用规模的增长,在移动Ad Hoc网络中支持多播路由成为网络领域中一类重要的研究课题。在MAODV的基础上,提出了一种采用基于优先权指数的竞争广播算法以及基于移动预测的主动路由维护机制的改进多播路由协议,仿真结果表明改进后的协议减少了开销、降低了时延,有效地增加了协议的可扩展性。     

基于OPNET的MAODV协议仿真实现及分析

移动Ad Hoc网络(MANET)的路由协议对网络的性能有较大影响,尤其在多播的场景下,好的多播路由协议可以节省大量无线传输带宽。MAODV路由协议是在AODV路由协议的基础上进行的多播扩展,也是目前MANET网络多播路由协议的研究热点。通过使用OPNET网络仿真软件,对MAODV协议进行仿真建模,使OPNET在MANET场景下支持多播路由协议的仿真,为其它需要MANET网络多播路由协议的场景提供支持。对仿真建模的结果进行了多方面的验证,以保证建模的正确性和有效性。     

A novel optimization-based bandwidth-aware minimum power multicast routing algorithm in green wireless networks

Multicast routing in wireless networks that possess the wireless multicast advantage could significantly reduce the power and energy consumption. However, this kind of multicast routing that only addresses the transmission radius coverage might not be able to meet the bandwidth requirement of the users. As a result, additional transmissions are required to incur more energy consumption and carbon dioxide emissions that make existing algorithms not applicable to bandwidth constrained applications. In this paper, for the first time, we address the bandwidth aware minimum power multicast routing problem in wireless networks where the objective function is to minimize the total power consumption subject to the users?? bandwidth requirements. This problem is a challenging cross-layer design problem that requires seamless and sophisticated integrated design in the network layer (multicast routing) and physical layer (bandwidth-aware wireless transmission and power control). We first formulate this problem as a mixed integer linear programming problem and then propose a Lagrangian relaxation based algorithm to solve this problem. Numerical results demonstrate that the proposed approach is a sound green networking algorithm that outperforms the existing power efficient multicast routing approaches under all tested cases, especially in large bandwidth request, fine radius granularity, large group size and sparse network.     

QMRPRNS: Design of QoS multicast routing protocol using reliable node selection scheme for MANETs

A mobile Ad-Hoc networks (MANETs) is a continuously self-configuring, infrastructure-less network of wireless mobile devices. In which multicast is one of the efficient way of communication. Currently, several research have been conducted to design multicast routing protocols for wireless mobile ad-hoc networks (MANETs). Multicasting is a technique that allow to send the same message to a group of destinations simultaneously. However, it faces several challenges against its implementation in ad-hoc network due to its dynamic nature, lack of bandwidth, short battery lifetime of the mobile devices. The multicast routing protocol MAODV have several constraints as mentioned above. Hence to address these constraints a reliable neighbour nodes selection scheme has been integrated over MAODV. This paper attempt a Quality of Service (QoS) based multicast routing protocol using reliable neighbour nodes selection scheme (QMRPRNS) for same. The simulation has been conducted to compare the performance of the proposed scheme against some existing multicast routing protocols which shows significant improvement over EMAODV and MAODV.     

Adaptive two-way uniform partition for multicast routing problem with separate paths in ad hoc networks

Finding a near-optimal routing solution for multicast requests is a challenge for supporting different multicast applications including video and group communications over wireless ad hoc networks. A heuristic partitioning algorithm for solving the multicast routing problem with separate paths in ad hoc networks is presented. We consider scheduling a set of multicast requests which may have a source node with multiple destinations respectively through a wireless network. Our heuristic method for partitioning arbitrary routing requests is both effective in finding a near-optimal solution, and efficient to solve large multicast requests. Our simulation shows that the average overall latency reduces up to 38%. We also find that the handling scales up well from 8 nodes to 64 nodes.     

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)。     

认知无线电网络中QoS组播路由调度

在多跳认知无线电网络中,组播的信息通常要经由多个中间节点的转发才能到达最终的目的节点。现有的研究中已经有很多的组播路由协议,然而这些协议都是基于传统无线网络的,并不适合新型的认知无线电网络。本文解决的的问题是:在多跳无线网络中,给定一个具有QoS要求的组播请求,如何建立组播路由以及对路径节点进行传输调度,使得在满足QoS要求下整个传输过程的带宽消耗最小。本文提出了一个分布式的组播路由协议来解决该问题,该协议不仅实现了路由过程的建立,同时还完成了对节点传输过程的合理调度。实验结果证明本文的传输调度策略能有效地减少网络的带宽消耗,同时增加组播请求响应的成功率。     

Ad hoc无线网络中的组播路由协议

由固定网络、基础结构移动网络和非基础结构无线网络组成的集成网络将成为未来互联网发展的趋势。同时,面向组计算和组通信的需求不断增长,要求未来的集成网络能为用户提供组播通信的功能。Adhoc无线网络是非基础结构无线网络的典型代表,具有带宽有限、拓扑结构易变和电池能源有限的特点,这些特性使得未来集成网络实现组播通信具有一定的挑战性。该文在分析Adhoc无线网络基本特性的基础上,综合评述了新近的Adhoc网络组播路由协议的研究现状,并对几种典型的Adhoc网络组播路由协议的特点进行了分类分析和比较,最后讨论了Adhoc无线网络组播路由协议的发展趋势和挑战。     

Research on multicast routing protocols for mobile ad-hoc networks

A mobile ad-hoc network (MANET) is composed of mobile nodes without any infrastructure. Mobile nodes self-organize to form a network over radio links. The goal of MANETs is to extend mobility into the realm of autonomous, mobile and wireless domains, where a set of nodes form the network routing infrastructure in an ad-hoc fashion. The majority of applications of MANETs are in areas where rapid deployment and dynamic reconfiguration are necessary and wired network is not available. These include military battlefields, emergency search, rescue sites, classrooms and conventions, where participants share information dynamically using their mobile devices. These applications lend themselves well to multicast operations. In addition, within a wireless medium, it is crucial to reduce the transmission overhead and power consumption. Multicasting can improve the efficiency of the wireless link when sending multiple copies of messages by exploiting the inherent broadcast property of wireless transmission. Hence, reliable multicast routing plays a significant role in MANETs. However, to offer effective and reliable multicast routing is difficult and challenging. In recent years, various multicast routing protocols have been proposed for MANETs. These protocols have distinguishing features and employ different recovery mechanisms. To provide a comprehensive understanding of these multicast routing protocols and better organize existing ideas and work to facilitate multicast routing design for MANETs, we present the taxonomy of the multicast routing protocols, their properties and design features. This paper aims to aid those MANETs researchers and application developers in selecting appropriate multicast routing protocols for their work.     

多播路由在无线网络中的OPNET建模与性能测试

多播路由技术凭借其有效节省网络带宽的优势,已成为研究无线多媒体网络服务质量(QoS)的热点内容。其中协议独立多播稀疏模式(PIM-SM)是域内多播路由协议中常见的协议。使用OPNET平台进行基于IEEE802.11无线局域网的仿真实验,首先对单播路由和PIM-SM多播路由在吞吐量上进行比较,实验结果表明多播路由在带宽的利用率上具有明显的优势。然后对文件传输、数据库访问、网络电话和视频会议等多媒体业务,进行单播路由和PIM-SM多播路由对比仿真实验,并且从延迟、延迟抖动和丢包率等方面给出结论,为真实无线多媒体网络环境的搭建提供一个很好的参考。     

组播协议在OPNET中的建模与仿真

该文以IP组播技术为重点,结合网络仿真软件OPENT Modeler,分析该软件环境下IP组播网络的建模机制,包括参考标准、组的管理、支持的应用、组播路由协议的选择,节点加入组播组与发送源发送组播数据的流程。以校园网视频会议和FTP传输应用为例,构建网络仿真模型,一方面比较单播与组播方式下的网络性能,分析了视频流量的发送情况、视频会议分组的端到端延时,FTP传输的响应时间,骨干网络点到点链路吞吐量;另一方面比较了组播方式采用共享树机制和由共享树切换到最短路径树在网络性能上的改进,包括分组延迟的降低、汇合点路由器上拥塞发生的减少等。同时,也对无线移动通信网络环境下的组播技术提出更多需要考虑的因素。