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1.
为了优化无线Mesh网络中的多接口多信道网络资源,对单接口多路径路由协议和单路径信道分配策略进行了深入的分析研究,提出了与混合式信道分配方式相结合的多路径路由协议(AODV-MP),实现了网络中多条路径的并行传榆,从而提高网络的整体吞吐率.并根据多路径路由协议自身的特性,结合与邻居节点干扰相关的因素--信噪比(SNR),提出了多路径路由的路由度量判决WCETYSNR,同时将该路由度量作为负栽流量分配的比例标准.利用NS2网络仿真平台对该多路径路由协议进行测试,结果显示AODV-MP在网络吞吐率上提高了45%,并在高负载情况下,较大幅度地减少了网络延时.  相似文献   

2.
闫茜  杨金程 《计算机应用》2010,30(9):2505-2508
为了优化无线Mesh网络中的多接口多信道网络资源,对单接口多路径路由协议和单路径信道分配策略进行了深入的分析研究,提出了与混合式信道分配方式相结合的多路径路由协议(AODV-MP),实现了网络中多条路径的并行传输,从而提高网络的整体吞吐率。并根据多路径路由协议自身的特性,结合与邻居节点干扰相关的因素——信噪比(SNR),提出了多路径路由的路由度量判决WCETTSNR,同时将该路由度量作为负载流量分配的比例标准。利用NS2网络仿真平台对该多路径路由协议进行测试,结果显示AODV-MP在网络吞吐率上提高了45%,并在高负载情况下,较大幅度地减少了网络延时。  相似文献   

3.
MANET中基于簇的多路径动态源路由(CMDSR)   总被引:6,自引:0,他引:6  
大量研究表明移动自组网(mobile ad hoc networks,MANET)的特性使得提高无线网络路由协议的可扩展性成为一个挑战性的工作.根据网络动态特性,提出了一个基于簇的多路径动态源路由机制(CMDSR),该机制利用分簇的层次结构来有效搜索多路径,利用多路径并行传输流量.协议的主要思想是在分簇算法中将网络分成单元簇(1-cell cluster)和中心簇(2-server cluster)两级层次结构,将路由发现程序放在2-server层来防止类似DSR路由发现过程的泛洪,实现路由开销最小化,提高网络的可扩展性,能够有效地处理节点数量增大和节点密度增大的问题.此外,CMDSR通过选择可靠的路径和发送端-端的可靠性软保证的方法解决了可靠性问题,因而具有良好的性能.在OPNET环境中实现了这个协议,结果表明,CMDSR能够平衡网络负载,有效地处理网络拓扑的易变性,从而有效地提高网络的可靠性和鲁棒性.  相似文献   

4.
MANET节点不相交多路径安全源路由协议   总被引:1,自引:0,他引:1  
多路径路由实现是移动Ad hoc网络(MANET)可靠运行的有效保证.现有MANET节点不相交多路径路由协议主要关注节点不相交多路径的可实现性和效率问题.针对节点不相交多路径路由协议MNDP协议在主动攻击者安全模型中的安全缺陷,提出了可证明安全的MANET节点不相交多路径动态源路由协议--SMNDP协议.SMNDP协议路由请求算法中,建立了中间节点路由请求消息传播策略的检错机制,SMNDP协议路由应答算法中建立了消息防篡改机制和身份认证机制.基于攻陷的网络拓扑模型,扩展了可模糊路由概念,提出了多路径可模糊路由集合概念和节点不相交多路径源路由协议的安全定义,并应用于SMNDP协议的安全分析.SMNDP协议的安全性可以归约为消息认证码和签名机制的安全性.  相似文献   

5.
为应对无线网络通信路径耦合性和相互干扰的问题,提高无线网络通信性能,提出应用于城市环境车用自组织网络的多路径通信路由协议.根据城市环境道路网络特点,建立车用自组织网络多路径通信干扰模型;在此基础上提出基于交叉路口优化多路径通信路由,交叉路口附近的数据包基于多路径策略转发.实验结果表明,该多路径路由机制减少了数据冗余,有效避免数据碰撞,较大程度提高网络的数据包投递率并降低端到端延迟.  相似文献   

6.
针对某些应用的高可靠性要求,设计并实现适合无线传感器网络(WSN)应用的多路径可靠路由协议。该路由协议通过建立备份路径,并在主路径失效的情况下采用备份路径传输数据的方法来提高数据传输的可靠性。该协议主要包括节点局部拓扑信息的获取、路由请求、节点主干路径的建立、Sink或中间节点发送路径增强信息建立备份路由、主路径失效后启用备份路径发送数据过程。仿真测试结果表明,该多路径可靠协议在主干路径失效的情况下,可以有效减小路径断裂引起的丢包现象,进而提高网络整体数据传输的可靠性。  相似文献   

7.
多路径路由能有效地增加网络的吞吐量以及平衡网络负载,结合移动自组网特点,提出了一种适合移动自组网的多路径QoS路由协议,该协议使用“软状态”方式进行资源预留,并在路由维护过程中使用了局部重构技术,有效地降低了协议的路由开销。模拟结果进一步表明,在动态的网络环境下,该多路径QoS协议能够有效地实现网络负载均衡,提高网络资源利用率,为移动自组网提供可靠而高效的传输性能。  相似文献   

8.
由无线信道的广播特性造成的路径之间的并行多径干扰问题,已经成为无线多媒体传感器网络中使用多路径路由必须解决的首要问题。针对该问题,提出了一种虚拟网格的干扰避免多路径路由协议(IAMVG)。该协议通过把监测区域划分为虚拟网格的方式,预先选择互不干扰的网格,进而优先选择该网格内的簇头节点加入路由的方法,尽量拉开相互干扰链路之间的距离,保证多路径路由处于相互的干扰区域范围外或者尽可能降低干扰。仿真实验表明,IAMVG路由协议极大地减少了并行多径干扰,保证了较高的通信成功率及较低的端到端时延。  相似文献   

9.
基于移动Ad Hoc网络的多路路由算法   总被引:1,自引:0,他引:1       下载免费PDF全文
移动Ad Hoc网络中有限的节点能量和带宽给路由协议设计带来了困难,对此考虑使用多路径机制来平衡负载,并提出了两种多路路由算法。其中,简单相关多路路由算法规定替换路径只能由主路径节点或其相邻节点构成,从而减小了替换路径的平均长度。仿真结果显示简单相关多路路由算法比节点不相关多路路由算法具有更好的性能,它将为无线网络中实现节能及可靠传输提供一种有效的途径。  相似文献   

10.
随着有线网络中多路径路由的部署和异构无线网络的发展,通信对等双方存在多条IP路径的场景越来越普遍.由于传统的单径传输协议无法充分发挥多路径带来的好处,如何设计有效的端到端多径可靠传输协议来提高端到端性能并保证网络资源分配的公平性成为研究的热点.多条路径的差异性给多径传输协议的设计带来诸多的问题:分组乱序造成接收缓存阻塞,不合理的多径分组调度造成吞吐率的抑制,缺乏多径协同造成带宽未充分利用和多径异构性造成网络资源分配不公平.就如何应对这些问题对现有协议多路径协议进行综述,并指出协议发展的趋势以及开放的研究问题.  相似文献   

11.
Multi-hop wireless networks (MHWN) have emerged to be a promising cost effective paradigm for the next-generation wireless technology. However, the unique characteristics of nowadays MHWN, such as distributed and dynamic network architecture, broadcast nature of wireless medium and stringent resource constraints of wireless devices, makes it extremely attractive and vulnerable to malicious attacks. So how to ensure continuous network service becomes a critical problem especially in jammed situations. Although some research has been conducted on countering jamming attacks, few works consider jamming dynamics. In this paper, interference avoidance mechanisms are well concerned and a proactive multi-path routing mechanism based on measuring jamming dynamic is presented. In our proposed solutions, the novel mechanism defines a new metric for routing known as the degree of interference activity (IA) to represent the jamming dynamic on a node. A comprehensive simulation study is conducted to evaluate the performance of the proposed scheme. Performance results show that our solution outperforms existing ad hoc routing protocols in terms of packet delivery and average end-to-end delay in the presence of jammers.  相似文献   

12.
Due to the energy and resource constraints of a wireless sensor node in a wireless sensor network (WSN), design of energy-efficient multipath routing protocols is a crucial concern for WSN applications. To provide high-quality monitoring information, many WSN applications require high-rate data transmission. Multipath routing protocols are often used to increase the network transmission rate and throughput. Although large-scale WSN can be supported by high bandwidth backbone network, the WSN remains the bottleneck due to resource constraints of wireless sensors and the effects of wireless interference. In this paper, we propose a multipath energy-efficient routing protocol for WSN that considers wireless interference. In the proposed routing protocol, nodes in the interference zone of the discovered path are marked and not allowed to take part in the subsequent routing process. In this way, the quality of wireless communication is improved because the effects of wireless interference can be reduced as much as possible. The network load is distributed on multiple paths instead of concentrating on only one path, and node energy cost is more balanced for the entire wireless network. The routing protocol is simulated in NS2 software. Simulation result shows that the proposed routing protocol achieves lower energy cost and longer network lifetime than that in the literature.  相似文献   

13.
在无线传感器网络中,现有的路由协议是基于静态位置数据路径的多播协议,路由路径的节点可能由于能源耗尽而死亡,因而缩短网络的生命周期.首先提出了一种动态位置的多播协议,以通过改变路由路径来平衡网络能耗,从而延长无线传感器网络的生命周期.此改进的协议平衡了能源,但信号的干扰是主要问题,因此有必要研究干扰的影响并给出对策.于是首次在此基础上引进了MR防干扰方法,增强了路由性能.仿真证明了基于MR防干扰下的高效能多播路由协议在能源消耗和抗干扰两个方面的性能改进.这特别适合于受干扰范围大的情况下又要求平衡能源消耗的情形,符合当前的研究趋势.  相似文献   

14.
Quality of service (QoS) routing is known to be an NP-hard problem in case of two or more additive constraints, and several exact algorithms and heuristics have been proposed to address this issue. In this paper, we consider a particular two-constrained quality of service routing problem maximizing path stability with a limited path length in the quest of improving routability in dynamic multi-hop mobile wireless ad hoc networks. First, we propose a novel exact algorithm to solve the optimal weight-constrained path problem. We instantiate our algorithm to solve the most stable path not exceeding a certain number of hops, in polynomial time. This algorithm is then applied to the practical case of proactive routing in dynamic multi-hop wireless ad hoc networks. In these networks, an adequate compromise between route stability and its length in hops is essential for appropriately mitigating the impact of the network dynamics on the validity of established routes. Secondly, we set up a common framework for the comparison between three families of proactive routing: the shortest path-based routing, the most stable path-based routing and our proposed most stable constrained path routing. We show then through extensive simulations that routing based on our proposed algorithm selects appropriate stable paths yielding a very high routability with an average path length just above that of the shortest paths.  相似文献   

15.
In wireless ad hoc networks, end-to-end delivery over network is a critical concern for routing protocols. The capacity of routing protocols is constrained by the intra-flow interference introduced by adjacent nodes on the same path, and inter-flow interference generated by nodes from neighboring paths. In this paper, we develop an on-demand routing protocol M-AODV-R that solves the channel assignment, reuse and routing problem jointly. The proposed channel reuse scheme and channel assignment scheme can enhance channel reuse rate. This cross-layer design approach can significantly improve the performance of multichannel ad hoc networks over existing routing protocols. Simulation results show that the proposed routing M-AODV-R can effectively increase throughput and reduce delay, as compared to AODV protocol.  相似文献   

16.
一般无线网络的路由协议不适合直接应用于认知无线电网络,需要提出一个新的路由算法以满足认知无线电网络端到端的服务质量(QoS)性能。认知无线电网络中的节点可以自主地进行信道选择和频谱切换,从而最大限度地满足流量需求和避免流内竞争。结合按需路由的基本流程,在充分考虑信道容量和流内竞争所带来的干扰对路由选择的影响下,提出了适用于认知无线电网络的基于容量和干扰的路由算法。仿真结果表明,基于容量和干扰的路由算法比另两种路由算法具有更好的端到端QoS性能。  相似文献   

17.
Hybrid Wireless Mesh Network (HWMN) is a new wireless networking paradigm. Unlike traditional wireless networks, in HWMNs, hosts may rely on each other to keep the network connected. Operators and wireless internet service providers are choosing HWMNs to offer Internet connectivity, as it allows fast, easy and affordable network deployments. One main challenge in design of these networks is their vulnerability to security attacks. In this paper, we investigate the main security issues focusing on the most vulnerable part of the hybrid WLAN mesh infrastructure which concerns the ad hoc network part. Through our proposed architecture, Security Architecture for Operator’s Hybrid WLAN Mesh Network (SATHAME), we identify the new challenges and opportunities posed by this emerging networking environment and explore approaches to secure users, data and communications. From the analysis of strengths and weaknesses of secured routing protocols, we designed a new robust routing structure called MacroGraph (MG). MG structure is extracted from the mesh ad hoc network for each communication to be established between a source and a destination. Especially, MG is a robust structure based on node-disjoint path routing scheme and dynamic trust management that can be adapted to respond to applications’ security requirements. We present a performance analysis of our efficient, robust and scalable multipath reactive secured routing protocol. We investigate the behavior of our proposed scheme under two attack scenarios: Packet Dropping and Route Error attacks in dense network configurations.  相似文献   

18.
The availability of bandwidth in wireless mesh networks (WMNs) introduces it as a prominent choice for implementing bandwidth sensitive services. Multicast services such as teleconferencing, push-based systems, multiplayer games, etc., can be implemented in an efficient way in such networks. Moreover, the severe performance degradations that can result from the interference generated by concurrent data transmissions and environmental noises call for the development of interference-aware routing mechanisms. This paper investigates the impact of wireless interference on network performance for multicast transmission in WMNs. We show that by taking wireless interference into consideration in the design of routing mechanisms, better resource usage can be achieved. Hence, a fuzzy logic–based approach is proposed to choose optimal routes from source to the multicast group in multichannel case. Three fuzzy variables are considered in route selection phase, which are interference, available bandwidth, and hop count. Extensive simulations are conducted aiming at verifying the high performance of the proposed algorithm. Simulation results demonstrated that our proposed algorithm outperforms Link-Controlled Multi-Rate Multi-Channel (LC-MRMC) and Channel Assignment with Multiple Factor (CAMF) algorithms in terms of throughput, packet delivery ratio, and end-to-end delay.  相似文献   

19.
主要研究了无线传感器网络路由路径的链路质量及节点剩余能量对网络整体可靠性及能效的影响,提出了无线传感器网络数据融合可靠路由的博弈论模型。该模型的求解属于NP问题,论文还提出了一种基于节点效用进行路由选择的分布式实现算法。仿真结果表明该算法能提高网络路由路径的可靠度和能效性。  相似文献   

20.
基于动态规划的无线传感器网络的路由算法   总被引:4,自引:2,他引:4  
路由问题是无线传感器网络中的核心问题之一,其数据传送的多跳特点使得非常适合用动态规划的原理来设计传感器网络的路由算法.基于动态规划,通过节点跳数生成算法为传感器网络中的每个节点赋一个表示到Sink点跳数的节点跳数值,并分析了传感器网络的拓扑结构特点,然后给出了无线传感器网络中寻找从源到汇满足不同设计目标的最小跳数(MinH)、最小跳数最大剩余能量(MinHMaxRE)和最小跳数最小费用(MinHMinC)3种路由算法.探讨了最小跳数最小费用路由与最小费用路由之间的关系,并给出了判断最小跳数最小费用路径就是最小费用路径的一个充要条件.算法的能量消耗分析表明,所给路由算法能实现大幅度的能量节省.  相似文献   

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