两种移动Ad Hoc网络协议及其性能比较

主要比较了两种移动Ad hoc网络路由协议——动态源路由协议和Ad hoc按需距离矢量路由协议。这两种协议虽然有一些共性,不过它们协议本身的特点导致在不同的网络负荷、节点移动性等条件下有明显的性能差异。这些性能差异通过实验结果得到进一步分析,并对如何改进两种协议给出建议。     

无线Ad Hoc网络路由协议及性能分析

Ad Hoc网络是一种由移动节点组成、拓扑结构动态变化的自组织网络.网络中没有固定的网络基础设施.由于移动主机的通信范围有限,相距较远的主机需要通过其他主机的"多跳"转发才能通信,因此网络中的主机同时也作为路由器为其他主机转发报文.目前设计的各种Ad Hoc路由协议大多数并没有具体的性能分析与比较.本文介绍几种典型的路由协议DSDV,TORA,DSR和AODV,利用Ns-2进行仿真,并对仿真结果进行分析.     

Ad Hoc网络中两种按需路由协议的比较

Ad hoc网络的特征是多跳的无线连接，网络拓扑的频繁变化，以及需要有效的动态路由协议。重点比较Ad hoc网络中两种主要的按需路由协议：动态源路由（DSR）协议和Ad hoc按需距离矢量路由（AODV）协议。尽管DSR和AODV都是按需路由协议，但不同的协议机制导致了网络性能的显著差异。在OPNET仿真平台下，对采用不用路由协议的网络时延和吞吐量进行比较，从而分析不同的路由机制引起的网络性能差异。     

Ad hoc网络两种按需路由协议性能分析

Ad hoc网络是一种无需依赖于事先布设的基础设施,而仅依靠网络内部节点之间的协作,就能够完成节点间通信的网络。比较了Ad hoc网络两种主流的按需路由协议：动态源路由协议,自组网按需距离矢量路由协议。使用基于ns-2的仿真模型进行仿真,并通过分组交付率、平均端到端时延、标准化路由负荷、对两种按需路由协议进行评估。实验结果表明即使DSR和AODV协议都是按需路由协议,但它们采取的路由机制的不同,导致它们的性能表现的巨大差异。     

Comparison of MANET Routing Protocols Using a Scaled Indoor Wireless Grid

Predicting the performance of ad-hoc networking protocols has typically been performed by making use of software based simulation tools. Experimental study and validation of such predictions is vital to obtaining more realistic results, but may not be possible under the constrained environment of network simulators. This paper presents experimental comparisons of routing protocols using a 7?×?7 grid of closely spaced WiFi nodes. It firstly demonstrates the usefulness of the grid in its ability to emulate a real world multi-hop ad-hoc network. It specifically compares hop count, routing traffic overhead, throughput, delay and packet loss for three protocols which are listed by the Internet Engineering Task Force Mobile Ad-hoc Networks (MANET) working group. These are the Ad-hoc on demand distance vector routing protocol (AODV), the optimized link state routing protocol (OLSR) and the dynamic MANET on demand routing protocol (DYMO).     

Performance Comparison Between p-i-n Tunneling Transistors and Conventional MOSFETs

In this paper, we present a detailed performance comparison between conventional n-i-n MOSFET transistors and tunneling field-effect transistors (TFETs) based on the p-i-n geometry, using semiconducting carbon nanotubes as the model channel material. Quantum-transport simulations are performed using the nonequilibrium Green's function formalism considering realistic phonon-scattering and band-to-band tunneling mechanisms. Simulations show that TFETs have a smaller quantum capacitance at most gate biases. Despite lower on-current, they can switch faster in a range of on/off-current ratios. Switching energy for TFETs is observed to be fundamentally smaller than that for MOSFETs, leading to lower dynamic power dissipation. Furthermore, the beneficial features of TFETs are retained with different bandgap materials. These reasons suggest that the p-i-n TFET is well suited for low-power applications.      

MANET路由选择协议性能分析

Ad hoc网是由一组无线移动节点在没有任何现存网络基础设施或集中管理的情况下建立的暂时的无线移动网络。由于网络节点的自组织性、多跳性和高速移动使得网络拓扑经常变化,导致路由开销增大。首先讨论了Ah hoc网络中路由选择协议的分类策略。介绍了几种典型的Ad hoc路由选择协议。通过ns2仿真工具,分析比较了DSDV、AODV和TORA等3种典型的ad hoc路由选择协议在不同环境下的性能,并给出了结论。     

Ad Hoc网络路由协议研究及其性能比较

介绍和分析了当前Ad Hoc网络中的主要路由协议算法,在Linux下使用网络仿真软件NS2评价Ad Hoc路由协议中的距离矢量路由协议、临时排序路由算法、动态源路由协议和Ad Hoc按需距离矢量路由协议,编写了用于仿真实现的脚本程序,并对仿真结果进行了分析比较和性能评价,由此得出不同协议的特性及其适用范围。     

基于战术互联子网的路由协议性能仿真比较

本文对基于移动Ad Hoc网络的营连以下战术互联子网的网络环境以及应用业务类型特点进行了分析,通过OPNET仿真软件对AODV、DSR和OLSR路由协议在CBR、FrP和Voice三种不同业务类型下进行了仿真,分析了路由协议的平均端到端延时、平均吞吐量和路由控制开销.仿真结果表明,在营连以下战术互联子网在进行战场态势感知任务时,AODV和OLSR协议性能较好;而进行语音话务任务时,OLSR比其AODV和DSR协议性能好.     

Ad hoc路由协议性能评价

在继承传统路由协议性能评价的基础上,提出了较为清晰合理的Adhoc网络路由协议性能评价标准,并对Adhoc两种较为典型的路由协议DSDV、AODV进行仿真及性能分析.仿真结果表明AODV的稳定性要好于DSDV,但在网络拓扑变化缓慢的环境中,DSDV的分组时延较短.     

WSN经典路由协议比较

本文首先介绍了WSN路由协议的特殊性、路由协议的分类等,然后针对WSN的几个经典路由协议,从协议的实现过程、协议特点、优缺点、适用领域等方面进行了分析,最后对这些路由协议的节能性、可扩展性、鲁棒性等方面进行了比较,以期为WSN路由协议的选用及进一步研究提供参考。     

A Comparison of the Performance Indices of Embedded EZ-Source Inverter Using Different PWM Techniques

Wireless Personal Communications - Many converters were proposed for boost/buck operation for power supply. But these converters have more stages due to separate boost or buck converters, as a...     

Performance Evaluation of Video Streaming Over Ad Hoc Networks Using Flat and Hierarchical Routing Protocols

A performance evaluation of real time services (such as video streaming) over mobile ad-hoc networks using both hierarchical and flat routing protocols is shown in this paper. A variety of workload and scenarios, as characterized by mobility, load and size of the ad hoc network have been simulated using NS-2. We use OLSR (Optimized Link State Protocol) as the flat routing protocol and our own implementation of HOLSR (Hierarchical OLSR)—which uses HNA (Host and Network Association) messages—as the hierarchical one, modifying other previous HOLSR version and maintaining the maximum compatibility with the flat OLSR. We carry out a complete comparison between these protocols focused on video evaluation. The simulation lets us compare the quality of service (QoS) of the video streaming paying attention to objective parameters (PSNR, packet delivery ratio, packet delay and interruptions). Some drawbacks of the hierarchical environment are also analyzed, as the link load between cluster heads and the lack of QoS-state-aware in HOLSR design. Quantitative results indicate that the protocol overhead is reduced (more than 40% in larger networks) and the video quality is improved (from 1 to 6 dB in certain cases) using hierarchical protocols.     

Query Localization Techniques for On-Demand Routing Protocols in Ad Hoc Networks

Mobile ad hoc networks are characterized by multi-hop wireless links, absence of any cellular infrastructure, and frequent host mobility. Design of efficient routing protocols in such networks is a challenging issue. A class of routing protocols called on-demand protocols has recently found attention because of their low routing overhead. We propose a technique that can reduce the routing overhead even further. The on-demand protocols depend on query floods to discover routes whenever a new route is needed. Our technique utilizes prior routing histories to localize the query flood to a limited region of the network. Simulation results demonstrate excellent reduction of routing overheads with this mechanism. This also contributes to a reduced level of network congestion and better end-to-end delay performance of data packets.     

基于OPNET仿真平台的MANET路由协议性能分析

MANET的特殊性决定了其路由协议的重要性。为了提高MANET路由协议性能,通过比较现有的两种典型MANET路由协议AODV协议和DSR协议,采用图形化界面的OPNET作为仿真工具,通过仿真结果的比较、分析,获得了与理论分析基本相一致的结果,即AODV协议的性能总体上优于DSR协议,并且AODV协议更适合于规模较大的MANET网络。仿真结果为后续提出优化路由协议和对现有协议改进工作提供了有效的仿真依据。     

Performance Evaluation of Routing Protocols for Ad Hoc Wireless Networks

A mobile ad hoc network is a collection of autonomous mobile nodes that communicate with each other over wireless links. Such networks are expected to play an increasingly important role in future civilian and military settings, being useful for providing communication support where no fixed infrastructure exists or the deployment of a fixed infrastructure is not economically profitable and movement of communicating parties is possible. However, since there is no stationary infrastructure such as base stations, mobile hosts need to operate as routers in order to maintain the information about the network connectivity. Therefore, a number of routing protocols have been proposed for ad hoc wireless networks. In this paper, we study and compare the performance of the following routing protocols AODV, PAODV (preemptive AODV), CBRP, DSR, and DSDV. A variety of workload and scenarios, as characterized by mobility, load and size of the ad hoc network were simulated. Our results indicate that despite its improvement in reducing route request packets, CBRP has a higher overhead than DSR because of its periodic hello messages while AODV's end-to-end packet delay is the shortest when compared to DSR and CBRP. PAODV has shown little improvements over AODV.     

Ad Hoc网络路由协议性能分析

介绍了移动自组网的表驱动和按需驱动两类路由协议.提出了定量评估网络路由协议性能的六个基本指标.利用网络仿真器NS-2,对四种典型的路由协议(DSR、DSDV、AODV和TORA)建立仿真模型,配置仿真参数,并进行了仿真.对仿真过程产生的文档进行处理,分析,比较它们的性能指标.试验结果表明,模型仿真结果接近理论分析和实际情况,该方法在路由协议研究,设计与仿真方面具有较强的实用性和通用性.     

移动Ad Hoc网络路由协议比较与分析

移动Ad Hoc网络是一个自组织系统,是由许多无线移动主机组成的一个临时动态网络,且不依赖于任何中心化的接入点和网络基础设施。对于这样一个网络,一个有效的路由协议对于适应主体的移动性以及为可能的链路提供可行的数据传输是非常必要的。限定路由协议的因素可归为两类,即无线传输过程中的衰退作用和网络拓扑的边缘效应。现存的各种路由协议着重从不同的角度来实现各自的功能。路由协议可分为两部分,路由发现和路由维护,而路由发现是其中的关键部分。     

A Novel High Performance Routing Algorithm for Mobile Multi-hop Tunneling Networks

Wireless Personal Communications - In recent years, the social internet of things (SIoT) has become a research hot topic in the field of wireless networks, which are inseparable relationships...