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1.
TANIYAMA Kenta MORII Takeshi KOIZUMI Shinya NOGUCHI Kazuhiro KOTANI Yukihiro KATTO Jiro 《浙江大学学报(A卷英文版)》2006,7(Z1)
We propose an on-demand multiparth routing algorithm in a mobile ad hoc network for video transmission and evaluate its real world performance in video streaming application. There have been a number of multipath routing protocols extended from AODV which is a well-known single path routing protocol. Multipath routing protocols indicate good performance in the reduction of route discovery latency and unnecessary routing packets in simulations. We show that the route establishment using source route lists provided by us (Hu and Johnson, 2002) can reduce the route discovery latency, select stable routes automatically, and work well for live video streaming without limitation of the hop count based approaches. We evaluate this proposed method compared with the original AODV by using eight laptop PCs and demonstrate live streaming experiments. 相似文献
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针对Ad Hoc网络路由问题,本文将备份路径加入到AODV（ad hoc on-demand distance-vector）路由协议中,使用原AODV中的RREP（Route Reply）控制信号和Data包来建立网状的备份路径,建立一种适应动态拓扑网络的路由协议,从而改善网络性能.采用面向对象的建模技术在OMNET＋＋软件平台上进行了仿真,结果证明该方法提高了网络的QoS,为Ad-hoc网络路由协议的发展提供了一个新思路. 相似文献
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在移动Ad Hoc网络环境中，链路失效和路由改变的事件经常发生．TCP应用在这样的环境中性能是低下的，因为它总是认为数据包的丢失是由于网络拥塞造成的．提出一种改进的AODV路由协议（E-AODV），此协议在选路时会选择一条稳定的路径，进而提高TCP的吞吐量．仿真结果表明E-AODV协议是有效的． 相似文献
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MANETs中基于链路有效性预测的高效AODV路由协议 总被引：1，自引：0，他引：1
针对传统AODV路由协议中周期性Hello消息广播机制会造成协议效率低下的问题,提出了一种利用无线链路有效性预测来降低Hello控制报文的新策略.首先给出了适用于视距无线传输环境下新的链路有效性预测模型,根据此模型所预测的无线链路生命周期来动态更新AODV路由协议中的Hello Interval配置参数,从而实现在不同链路稳定性下以不同频率广播Hello消息的目的.仿真结果表明,相比于采用周期性Hello消息广播机制的原协议而言,改进协议有效减少了不必要的报文开销,并在平均端到端时延和协议效率这2个性能指标上都获得了明显改善. 相似文献
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Ad Hoc网络是目前无线网络的一个流行趋势,但作为一种新兴无线网络,因其自身的特点,传统有线网络的安全技术并不完全适用于它,因此Ad Hoc网络的安全问题一直是一个研究的热点问题。深入分析了AODV协议及其路由发现、路由维持和路由修复过程。在此基础上,本文基于AODV协议提出了一种基于信任的安全路由协议(TBS-AODV),利用NS2仿真器对TBS-AODV协议进行了仿真,其结果表明TBS-AODV协议在付出一定的消耗代价后可以较好的避免灰洞、黑洞等攻击,可以实现安全可信的路由。 相似文献
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Low energy consumption is one of the main challenges for wireless video transmission on battery limited devices. The energy invested at the lower layers of the protocol stack involved in data communication, such as link and physical layer, represent an important part of the total energy consumption. This communication energy highly depends on the channel conditions and on the transmission data rate. Traditionally, video coding is unaware of varying channel conditions. In this paper, we propose a cross-layer approach in which the rate control mechanism of the video codec becomes channel-aware and steers the instantaneous output rate according to the channel conditions to reduce the communication energy. Our results show that energy savings of up to 30% can be obtained with a reduction of barely 0.1 dB on the average video quality. The impact of feedback delays is shown to be small. In addition, this adaptive mechanism has low complexity, which makes it suitable for real-time applications. 相似文献
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Low energy consumption is one of the main challenges for wireless video transmission on battery limited devices. The energy invested at the lower layers of the protocol stack involved in data communication, such as link and physical layer, represent an important part of the total energy consumption. This communication energy highly depends on the channel conditions and on the transmission data rate. Traditionally, video coding is unaware of varying channel conditions. In this paper, we propose a cross-layer approach in which the rate control mechanism of the video codec becomes channel-aware and steers the instantaneous output rate according to the channel conditions to reduce the communication energy. Our results show that energy savings of up to 30% can be obtained with a reduction of barely 0.1 dB on the average video quality. The impact of feedback delays is shown to be small. In addition, this adaptive mechanism has low complexity, which makes it suitable for real-time applications. 相似文献
8.
移动自组织网络（Mobile Ad hoc Network,MANET）的一个典型特点就是网络拓扑结构的动态变化,这个特点造成了在通信过程中路由的频繁切换。而路由频繁切换的过程往往会给上层的服务应用带来不利影响。以在移动场景中综合性能最优的AODV（Ad hoc on-demand distance vector）协议为研究对象,通过NS2仿真分析了在一个连接运行过程中路由切换的特点,包括路由切换的触发原因、切换时延、切换丢包率等因素。该文对路由切换性能的详细分析结果为将来优化路由维护策略及提升路由切换效率提供了参考和依据。 相似文献
9.
A load-balanced minimum energy routing algorithm for Wireless Ad Hoc Sensor Networks 总被引：3，自引：0，他引：3
CAI Wen-yu JIN Xin-yu ZHANG Yu CHEN Kang-sheng 《浙江大学学报(A卷英文版)》2006,7(4):502-506
INTRODUCTION Wireless Sensor Network is one special type of wireless ad hoc networks without fixed infrastructure consisting of a collection of sensor nodes, and oper- ating on limited amount of battery energy consumed mostly in transmission and reception. In the WSNs described in Fig.1, every sensor node can sense, process data and communicate to base station (BS). WSNs have attracted much attention during the recent two years and some commercial implementations such as environmental … 相似文献
10.
An adaptive load balancing scheme is proposed to balance the load in ad hoc networks. The new scheme can be applied in most on-demand routing protocols resulting in significant performance improvement. The proposed scheme is applied to the ad hoc on-demand distance vector (AODV) routing protocol. Simulation results show that the network load is balanced on the whole, and performance in packet loss rate, routing overhead and average end-to-end delay is also improved. 相似文献
11.
针对Adhoc网络中移动节点能量受限的问题,考虑节点剩余能量和节点能量消耗速率两方面因素,对AODV协议,在选路机制,hello机制几个方面作了改进,改进后的路由协议能够有效均衡负载,保护低能量节点,延长网络生存时间。 相似文献
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In this paper we introduce a novel energy-aware routing protocol REPU （reliable, efficient with path update）, which provides reliability and energy efficiency in data delivery. REPU utilizes the residual energy available in the nodes and the received signal strength of the nodes to identify the best possible route to the destination. Reliability is achieved by selecting a number of intermediate nodes as waypoints and the route is divided into smaller segments by the way-points. One distinct advantage of this model is that when a node on the route moves out or fails, instead of discarding the whole original route, only the two way-point nodes of the broken segment are used to find a new path. REPU outperforms traditional schemes by establishing an energy-efficient path and also takes care of efficient route maintenance. Simulation results show that this routing scheme achieves much higher performance than the classical routing protocols, even in the presence of high node density, and overcomes simultaneous packet forwarding. 相似文献
14.
针对标准AODV路由协议中,目标节点选择一条端到端跳数最小的路径作为源节点到目标节点的路径,而采用最小跳路由的路由协议所选的路径在某些情况下并非最优路径的问题。提出选择一条数据传输速率高的路径,作为源节点到目标节点的路径,称为HDR_AODV协议。设计了HDR_AODV协议的RREQ和RREP分组格式,在OPNET上实现了HDR_AODV的功能,并且通过实验。结果表明,从延时、吞吐量、丢包数量等网络性能评测参数HDR_AODV的性能要优于标准AODV。 相似文献
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本文提出了适用于物联网视频多跳中继无线通信的实现能量预估的网络层叠协同路由交互寻访技术。该技术的前提是采用遗传算法设计轮询步进优化估值模型,依据估值模型计算节点感知距离和节点能量,结合无线大容量信号编码解调码过程建立层叠协同交互寻访体系,优化簇内、簇头节点的传输效能,实现用户层、网络通信层和感知层层叠路由的交互协同。经软件仿真和数学矩阵对比,该技术可较好地满足物联网视频等大容量感知数据的传输与处理,而且可以充分利用物联网层叠资源特别是感知层与链路层受限的运算、存储和能量等资源。 相似文献
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无线传感器网络是一种无线自组织网络,路由协议是保证它能正常运作、高效传输信息的不可或缺的部分．本文采用仿真软件NS-2对洪泛式路由协议及定向扩散协议进行了仿真研究．与洪泛式路由协议相比较,定向扩散协议在能量消耗与延时性这两方面性能较好,更适合于无线传感器网络的应用环境． 相似文献
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在移动Ad Hoc自组织网络环境中,路由算法是影响网络服务质量的关键问题。本文重点对无线网络环境下路由算法进行研究和分析,并对AODV算法进行了改进,经过理论分析和仿真实验,证明该方法是有效的。 相似文献
18.
机会网络是一种通过节点移动建立通信链路的无线自组织网络,一般通过消息复制的路由策略传递信息。但该方式将导致链路中存在大量消息副本,对节点缓存形成巨大压力,造成网络拥塞。针对该情况,结合Prophet算法,充分考虑节点缓存对链路状态及传输概率的影响,设计限制消息最大副本数量与及时删除节点缓存中不必要数据包的缓存管理机制,同时在Prophet算法中考虑了缓存比因素。仿真结果表明,该算法可以有效提高消息投递率,降低网络消耗。 相似文献
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ZigBee无线传感器网络树状路由协议研究 总被引：1，自引：0，他引：1
介绍了基于IEEE802.15.4和ZigBee标准的无线传感器网络协议,给出了ZigBee网络的地址分配方法,然后描述了用于ZigBee网络的路由协议：树状路由和网状路由,在此基础上详细分析了树状路由协议,包括网络层帧格式、路由算法.最后建立了一个簇树网对树状路由协议进行测试,证明树状路由的可靠传输,为基于ZigBee簇树网的无线传感器网络的开发应用提供有价值的参考. 相似文献
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无线Mesh网络作为一种新型的无线网络,路由协议对网络整体性能起着至关重要的作用。分析目前基于无线MeshN络的三种典型路由协议DSR、AODV及DSDV,利用仿真软件NS2比较这三种协议在分组成功投递率、平均时延、路由开销以及选择较优路径方面的性能表现,结果表明,按需路由协议DSR在分组成功投递率、平均时延、路由开销以及选择较优路径方面较AODV、DSDV有较好表现。 相似文献