共查询到19条相似文献,搜索用时 463 毫秒
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针对无线传感器网络环境下低功耗路由问题,根据无线传感器网络是一种以数据为中心的网络的特点,提出了一种基于内容的低功耗路由协议CBP。其基本思想是:Sink节点根据上层应用构造谓词,并对谓词进行广播,网络中所有传感节点以Sink节点的谓词为依据建立路由表,实现数据路由。与现有无线传感器网络路由协议相比较,此路由协议具有低功耗,占用节点资源少,网络容错能力强等特点。仿真结果表明,在节点数量大于100的大规模网络中,基于内容的无线传感器网络路由协议功耗比定向扩散协议功耗降低19%。 相似文献
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《中国激光》2017,(10)
为了改善紫外光(UV)点对点通信中传输距离有限、覆盖范围小的问题,组建了UV自组织(Ad Hoc)网络。结合UV通信的信道特性,提出了一种UV组网通信收发装置设计方案。基于该方案,给出了UV Ad Hoc网络节点定位算法,该算法利用节点间的通信距离和扇区信息求得节点间的相对位置。以无线Ad Hoc网络多播按需距离矢量路由协议为基础,提出了一种UV空分复用Ad Hoc网络路由协议,并对该路由协议进行了仿真,给出了不同节点数和运动区域下的仿真结果。结果表明:在满足发包数、时延和丢包率等通信要求的前提下,在一定运动区域内,应选择较少的节点;当节点数一定时,应选择较小的运动区域。 相似文献
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简要介绍了Adhoc网络中路由协议的特殊性,指出节点能量是Adhoc网络中影响系统路由生存时间的关键性因素,常规无线路由协议的建立大多数是基于源一目的节点跳数多少的的基础上,提出一种基于节点能量高低来优先建立路由的协议DDSR,并利用NS2软件对DSR、DDSR进行仿真,结果显示DDSR相对于DSR提高了系统生存时间。 相似文献
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本文简要介绍了Ad hoc网络中路由协议的特殊性,指出节点能量是Ad hoc网络中影响系统路由生存时间的关键性因素。在无线按需路由协议DSR的基础上,提出一种基于节点能量高低增加延时函数来选择路径的协议EDSR。仿真结果显示EDSR相对于DSR提高了系统生存时间。 相似文献
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Cluster‐based data dissemination,cluster head formation under sparse,and dense traffic conditions for vehicular ad hoc networks 下载免费PDF全文
Kashif Naseer Qureshi Abdul Hanan Abdullah Faisal Bashir Saleem Iqbal Khalid Mahmood Awan 《International Journal of Communication Systems》2018,31(8)
Information and communication technologies have changed the way of operations in all fields. These technologies also have adopted for wireless communication and provide low cost and convenient solutions. Vehicular ad hoc networks are envisioned with their special and unique intercommunication systems to provide safety in intelligent transportation systems and support large‐size networks. Due to dense and sparse traffic conditions, routing is always a challenging task to establish reliable and effective communication among vehicle nodes in the highly transportable environment. Several types of routing protocols have been proposed to handle high mobility and dynamic topologies including topology‐based routing, position and geocast routing, and cluster‐based routing protocols. Cluster‐based routing is one of the feasible solutions for vehicular networks due to its manageable and more viable nature. In cluster‐based protocols, the network is divided into many clusters and each cluster selects a cluster head for data dissemination. In this study, we investigate the current routing challenges and trend of cluster‐based routing protocols. In addition, we also proposed a Cluster‐based Routing for Sparse and Dense Networks to handle dynamic topologies, the high‐mobility of vehicle nodes. Simulation results show a significant performance improvement of the proposed protocol. 相似文献
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Vehicular Adhoc Network (VANET) is playing a vital role in recent research. Designing an effective routing protocol for VANET is a challenging task as the VANET nodes move very fast. The design of the routing protocol normally is particular to the specific topology. This paper proposes CLMR, a multipath routing protocol based on cross layer design and also using Redundant Array Inexpensive Disks (RAID). Cross layer is designed among application, network, Media Access Control, and physical layers. It is employed to reduce the end to end delay in network, and RAID is used to minimize the number of re‐transmissions. Three variations of RAID 1 are implemented—Distributed Parity along Single path, Double Distributed Parity, and Distributed Parity among Multiple paths. Multipath routing protocol based on cross layer‐Distributed Parity along Single path recovers 1 packet loss per parity packet along the corresponding path, CLMR‐Double Distributed Parity recovers 2 packets per parity packet along the corresponding path, and CLMR‐Distributed Parity among Multiple paths recovers the packets of the failed path. The evaluation is carried out to test the Quality of Service parameters‐end to end delay, throughput, packet delivery ratio, and number of retransmissions. The results projected show that the CLMR performs better when compared with the legacy protocol Adhoc On‐demand Multipath Distance Vector Routing. 相似文献
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无线网状网(WMN)相关技术的研究非常活跃,路由判据的设计是提高其性能的关键。WMN具有同时拥有移动节点和静态节点及每个节点可能配置多信道等特点。对路由判据的设计提出了特别的要求:必须保证网络的稳定性;保证最小权重路由有最佳性能;该路由可以通过多项式复杂度算法得到;得到的路由中无转发环路。研究了几种现有的路由判据,包括HOP、ETX、ETT、WC-ETT、MIC、mETX、ENT。MIC能较好适应WMN,但需要在自由因子的设定及网络中加入移动节点后的性能方面做改进。对路由判据的跨层、多准则设计是以后的研究方向,基于此文中也对几个改进方案进行分析。 相似文献
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Ad hoc网络是一种无有线基础设施支持的移动网络,它与internet相比存在许多差异,不仅有网络拓扑结构的不同,还存在通信方式的不同,因此两者的互联是一具有挑战性的课题。Adhoc网络结点要进行internet连接,必须寻找internet网关,如何发现和维持与网关的连接以及如何切换到一个更合适的相邻网关是这个问题的关键。文章在主动式、被动式、混合式及AODV路由协议中Hello消息机制的基础上,讨论了一种新的网关发现方法,即利用Hello消息机制,通过改进网关和节点对Hello消息的处理所得到的新的网关发现机制,仿真结果显示在一定网络环境下能够基本满足adhoc接入internet的需要。 相似文献
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Implementation of depth‐based routing and its enhancement in AquaSim–Next Generation for underwater wireless sensor networks 下载免费PDF全文
Mohsin Jafri Simonetta Balsamo Andrea Marin Robert Martin 《International Journal of Communication Systems》2018,31(12)
In the last decade, underwater wireless sensor networks have been widely studied because of their peculiar aspects that distinguish them from common terrestrial wireless networks. Their applications range from environmental monitoring to military defense. The definition of efficient routing protocols in underwater sensor networks is a challenging topic of research because of the intrinsic characteristics of these networks, such as the need of handling the node mobility and the difficulty in balancing the energy consumed by the nodes. Depth‐based routing protocol is an opportunistic routing protocol for underwater sensor networks, which provides good performance both under high and low node mobility scenarios. The main contribution of our work is presenting a novel simulator for studying depth‐based routing protocol and its variants as well as novel routing protocols. Our simulator is based on AquaSim–Next Generation, which is a specialized tool for studying underwater networks. With our work, we improve the state of the art of underwater routing protocol simulators by implementing, among other features, a detailed cross‐layer communication and an accurate model of the operational modes of acoustic modem and their energy consumption. The simulator is open source and freely downloadable. Moreover, we propose a novel and completely distributed routing protocol, named residual energy–depth‐based routing. It takes into account the residual energy at the nodes' batteries to select the forwarder nodes and improve the network lifetime by providing a more uniform energy consumption among them. We compare its performance with that of depth‐based routing protocol and a receiver‐based routing protocol implementing a probabilistic opportunistic forwarding scheme. 相似文献
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对网络状态信息的处理是路由的基础。随着因特网服务业务的日益丰富,实现服务的策略面临新的挑战。其中,智能路由是应对这一挑战的策略之一。智能路由包括网络状态信息收集和处理的智能化、路由机制的智能化等方面。本提出以知识处理为基础的智能路由策略,在从知识处理的角度对网络状态信息、基本路由运算操作进行分析的基础上,简要介绍了实现智能处理的基本途径.以及在开放系统中支持路由计算的知识处理的主要理论和技术。 相似文献
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Wireless Personal Communications - Mobile Adhoc networks (MANETs) is new exemplar of wireless networks which has some unparalleled features such like dynamically altering topology, baseless... 相似文献
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Multipath routing mechanism is vital for reliable packet delivery, load balance, and flexibility in the open network because its topology is dynamic and the nodes have limited capability. This article proposes a new multipath switch approach based on traffic prediction according to some characteristics of open networks. We use wavelet neural network (WNN) to predict the node traffic because the method has not only good approximation property of wavelet, but also self-learning adaptive quality of neural network. When the traffic prediction indicates that the primary path is a failure, the alternate path will be occupied promptly according to the switch strategy, which can save time for the switch in advance. The simulation results show that the presented traffic prediction model has better prediction accuracy; and the approach based on the above model can balance network load, prolong network lifetime, and decrease the overall energy consumption of the network. 相似文献
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《Digital Communications & Networks》2017,3(3):195-210
Extensive investigation has been performed in location-centric or geocast routing protocols for reliable and efficient dissemination of information in Vehicular Adhoc Networks (VANETs). Various location-centric routing protocols have been suggested in literature for road safety ITS applications considering urban and highway traffic environment. This paper characterizes vehicular environments based on real traffic data and investigates the evolution of location-centric data dissemination. The current study is carried out with three main objectives: (i) to analyze the impact of dynamic traffic environment on the design of data dissemination techniques, (ii) to characterize location-centric data dissemination in terms of functional and qualitative behavior of protocols, properties, and strengths and weaknesses, and (iii) to find some future research directions in information dissemination based on location. Vehicular traffic environments have been classified into three categories based on physical characteristics such as speed, inter-vehicular distance, neighborhood stability, traffic volume, etc. Real traffic data is considered to analyze on-road traffic environments based on the measurement of physical parameters and weather conditions. Design issues are identified in incorporating physical parameters and weather conditions into data dissemination. Functional and qualitative characteristics of location-centric techniques are explored considering urban and highway environments. Comparative analysis of location-centric techniques is carried out for both urban and highway environments individually based on some unique and common characteristics of the environments. Finally, some future research directions are identified in the area based on the detailed investigation of traffic environments and location-centric data dissemination techniques. 相似文献