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1.
Ad-hoc路由协议依据路由发现的不同分为主动路由策略和按需路由策略,根据实际网络特点,结合两类协议的优点,提出一种适合快速拓扑更新的无线路由协议。并采用SDL语言工具设计验证了这种小型高移动性无线网络的路由协议。  相似文献   

2.
针对Ad-hoc网络在路径选择上主要选择最短路径所出现的问题,从复杂适应系统理论的角度出发,将基于概率推理的路径选择算法加入到AODV(Ad hoc on-demand distance-vector)路由协议中,通过对节点的适应度进行概率推理来选择路径,有效地解决了Ad-hoc网络的拥塞和负载分配问题,改善了网络性能。采用面向对象的建模技术在OMNET++软件平台上进行仿真,结果证明该方法降低了延迟时间,提高了网络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   

3.
刘方斌  张琨  张宏 《计算机科学》2011,38(11):48-53
Ad-hoc网络节点运算能力差,能量有限且移动速度高,而公钥运算量大,能耗高,运算周期长,所以公钥运算不适合于Ad-ho。网络。已提出的匿名路由协议却含有大量的公钥运算。为了降低公钥运算量,将双线性对和零知识证明应用于匿名路由协议中,提出一种新的匿名路由协议—低运算量的Ad-hoc网络匿名路由协议,该协议大幅降低了公钥运算量。实验结果表明,该协议建立匿名路由所消耗的能量少,时延低。  相似文献   

4.
根据Ad-hoc移动网络特点,深入分析了串空间模型的一致性条件,提出路由五段式模型,将中继者可信条件修改为任意中继者可信条件,使串空间适用于Ad-ho。安全路由协议分析。然后以一个攻击实例验证路由五段式模型的正确性和优越性。  相似文献   

5.
Ad-hoc网络路由主要研究从源和目的点之间找到一条连接的路由,经常忽略网络的QoS需求,如果数据流量超过了该网络所能承受的最大限度,Ad-hoc网络将不能保证数据流的传输质量。因此提出了一种改进的QoS-AOMDV路由协议,在AOMDV路由基础上增加了带宽、时延、跳数和优先级等约束条件,使得在路由发现和路由维护阶段满足一定的QoS需求。仿真结果显示,在多径路由协议可以保证通信服务质量。  相似文献   

6.
移动Ad-hoc网络是一种新颖的无线对等网络,随着无线终端设备(便携式电脑、PDA等)的日益普及,Ad-hoc网络在军事、商业、个人区域网络(PAN)及分布式Ubiquitous计算环境下均有非常广泛的应用前景。路由协议的安全性问题是Ad-hoc网络成为实用性技术前必须妥善解决的关键问题之一。文章提出了一种新的基于网络安全环境的Ad-hoc网络分类方法,并以此为基础制定了强制协作式安全和激励式安全两类基本安全策略,建议Ad-hoc网络中的路由安全机制应该根据安全环境的分类采用相应的安全策略进行设计,而不是人为假设安全机制的前提条件。  相似文献   

7.
传统的无线Mesh网络(WMN)路由协议利用路由管理帧携带的路由信息来维护路由。无线环境的不稳定性可能导致路由管理帧丢失,使路由协议无法及时获取正确的路由信息,从而降低网络性能。介绍了一种基于统计学原理的无线Mesh网络路由协议B.A.T.M.A.N.(Better Approach To Mobile Ad-hoc Networking) 。该协议通过统计路由管理帧的投递成功率来选择最优路径,消除了路由管理帧丢失对路由协议的影响。通过与OLSR的测试对比表明,B.A.T.M.A.N.在无线Mesh网络中有更好的性能表现,更适用于移动网络。  相似文献   

8.
为了提高在Ad Hoc上实时视频传输质量,改进现有的信道切换算法并应用到AOMDV(Ad-hoc on-demandMultipath distance vector)协议,得到一个新的路由协议:MIMC-AOMDV(multi interface multi channel AOMDV)路由协议;针对影响视频传输质量的网络性能指标,进一步采用区分视频服务的时延QoS约束和跨层的链路质量度量改进MIMC-AOMDV路由协议得到新协议:QMMIMC-AOMDV(quality metric MIMC-AOMDV);通过扩展实验平台并用仿真实验验证了所提出的改进思想的可行性和有效性。实验结果表明,所提出的QMMIMC-AOMDV协议能有效降低帧时延,提高帧可解码率和峰值信噪比(peak signal to noise ratio,PSNR),更适合于实时视频流的传输。  相似文献   

9.
介绍了当前Ad Hoc(移动自组网络)的网络路由协议研究现状,对Ad Hoc网络路由协议分类,并就传统的按需距离矢量路由(Ad-hoc On-Demand Distance Vector routing,AODV)的特征、优点和缺点给出分析,提出了一个新的基于AODV的改进路由协议--N-AODV(Neighborhood Routing Protocol based on AODV).采用NS-2系统仿真工具搭建了移动Ad Hoc网的仿真平台,在此平台的基础上,实现了N-AODV路由算法.通过仿真比较传统的AODV路由算法和改进的AODV路由算法的网络性能,验证了N-AODV算法的可行性,为实际系统的设计和规划提供了参考算法、参考模型和参考数据.最后,提出了一个基于Ad Hoc网络应用的系统架构.  相似文献   

10.
Ad-hoc网络多径路由协议的研究与设计   总被引:2,自引:0,他引:2  
对目前典型的Ad-hoc网络按需多径距离矢量路由协议(AOMDV)进行了研究和优化设计.优化后的协议(Op-AOMDV)保留了原协议中建立多径无环路由的思想,改进了原协议中建立链路不相交路由等不完善的部分,给出了原协议中未提及的细节,降低了协议的复杂性,提高了协议的可实现性.  相似文献   

11.
Several approaches have been proposed for designing multihop routing protocols in mobile ad hoc networks (MANET). Many of them adopt a method, called flooding, to discover a routing path. Due to the time-varying nature of the route in MANET, the discovered route needs to be dynamically maintained for optimality in terms of traffic load, hop-distance, and resource usage. It is easy to see that flooding incurs significant overhead and hence is inappropriate for the dynamic route maintenance. In this paper we propose a randomized, dynamic route maintenance scheme for adaptive routing in MANET. The scheme makes use of a nomadic control packet (NCP) which travels through the network based on a random walk, and collects its stopovers as a traversal record. The NCP uses the traversal record to probabilistically provide the nodes with clue for routing path updates. From the clue, the nodes can find the routing path update information that is up-to-date and optimal (less-loaded and shorter), thereby adapting to the dynamic network topology and traffic load conditions. We present an analytical model for measuring the effectiveness of NCP in terms of its frequency of visits and probability of finding the clue from the NCP traversal record. The proposed randomized scheme serves as a routing protocol supporting layer and can be easily applied with minimum modifications to the existing on-demand routing protocols such as AODV and DSR. In our experimental study, we modified the AODV protocol to maintain routing paths using NCPs’ traversal record. Simulation results show that NCPs help the routing protocol to notably reduce average end-to-end packet delay with increased route optimality and better control on traffic congestion.  相似文献   

12.
在移动自组织网络(MANET)的研究中,一般采用软件仿真和现场试验的方式对所设计的路由协议进行验证。软件仿真常用来对路由协议的原理和性能进行初步验证,现场试验则常用在开发过程中的测试和产品上线之前的最终验证。在MANET的路由协议开发过程中采用现场试验的方式进行测试其结果虽然准确可靠,但是试验成本较高、操作相对较为复杂,并且试验结果容易受到地理环境等外界因素的影响。针对上述情况,本文提出一种基于有线以太网构建MANET网络试验床的方法,并基于VxWorks实时操作系统,设计和实现一个接近于真实试验环境的MANET网络试验床。该试验床对标准的TCP/IP协议栈进行扩展,在网络层和数据链路层中间添加模拟无线链路层,从而在有线链路上模拟节点移动、无线信道通信等MANET网络特性。此外,试验床还可以通过管控平台配置不同测试场景,并可以实时采集网络协议栈的各层试验数据,从而方便网络研究人员进行测试和验证。该试验床克服了现场试验成本高、操作复杂等缺点,解决了现场试验过程中很难对问题场景进行重现的问题,明显减少了试验时间,提高了开发效率。  相似文献   

13.
一种基于邻居信任评估的虫洞防御机制   总被引:6,自引:0,他引:6  
洪亮  洪帆  彭冰  陈晶 《计算机科学》2006,33(8):130-133
移动adhoc网是一种新型无线移动网络,具有无中心、自组织、拓扑结构变化频繁以及开放式通讯信道等特性,因此adhoc网络下的路由协议所面临的安全问题比有线网环境中更为严重。虫洞攻击就是其中的一种,能够对adhoc网络产生致命的影响。在这种攻击下,网络的路由机制将会紊乱,特别是那些依赖通过接收对方的广播报文进行邻居探测的路由协议。本文首先从虫洞形成的根源上入手,重新定义了邻居的概念,强调了邻居作为节点信息转发第一站的功能。然后根据邻居定义,引入简化的Marsh信任模型,将邻居的以往表现作为信任评估的经验来源,再通过具体公式对邻居关系做出判定。在具体的路由过程中,节点根据信任评估值选取高可信度的邻居作为下一跳的转发节点,从而避免虫洞攻击的危害。为了验证方法的可行性,本文将模型应用于OLSR路由协议中并在NS2中进行了仿真。  相似文献   

14.
In MANET network management, the Software-Defined Networking (SDN) plays a vital role in terms of controller plane and data plane. It is always easy to manage the data communication over the MANET because of logically centralized control on the SDN. Since the dynamic route on MANET, are controls the packets and changes the route between the source to destination alternatively. Hence the maintenance of real-time SDN analysis-based application planes is a crucial process. To maintain the effective MANET communication over the Software-Defined Network, it essential to improve the control and data plane process on the SDN controlled MANET based OpenFlow switching procedure. Nevertheless, SDN allows for route interaction against security threads. In this research article, the four stages were suggested to preserve the security measures in packet-based data transmission that are conceived in MANET. In this article, an SDN controlled MANET based OpenFlow switching scenario for effective security threading is proposed. The major part played by an SDN controlled MANET in bringing about a result of being effective without wasting time and energy on routing. The proposed Distinct Network Yarning (DISNEY) routing protocol for SDN controlled MANET overcomes the congestion communication on MANET routing. To decrease performance degradation, efficient routing is maintained by the route matrix manipulation table. This routing scheme helps to find the optimal routing with a secure and intelligent manner. The proposed result was compared to existing approaches. As a result, the proposed illustration to be improved by routing and data transmission. In comparison to the proposed method achieves a better ratio for packet transmission delay, throughput, and data transmission rate.  相似文献   

15.
对移动自组网的拓扑结构进行分析,建立其路由网络模型.将遗传算法的基本原理和移动自组 网的路由模型结合起来,提出了一种求解无线网络最优路径的算法.该方法采用可变长度染色体编码,利用 遗传算法优化路由,可以在满足系统开销最小的约束条件下寻找到最优路径.  相似文献   

16.
随着UWB技术的出现,无线移动多媒体业务在自组网中的应用成为可能。为了满足无线移动多媒体传输的需要,设计了一种新的针对多媒体业务的QoS路由协议,给出了协议的详细描述。由于该协议充分利用了UWB技术的速率和距离互换特性,考虑了传输速率、时延和链路拥塞程度3个QoS参数,并借鉴无线移动自组网基本路由协议DSR和AODV,因此不仅能够获得满足业务要求的路由,且能提前预测链路的中断,以便及时切换替代路由。与目前已提出的基于UWB技术的路由协议相比,该协议更适合于无线移动多媒体业务的传输。  相似文献   

17.
In the doorway of the Mobile IPv6 (MIPv6), it was considered as the standard protocol that support the host mobility. Due to its limitation that does not support the mobile routers (MRs), the Internet engineering task force (IETF) has introduced the NEMO basic support (NEMO BS) protocol. The mobile ad hoc network (MANET) routing protocol provides the local and the direct communications between two mobile devices within the nested NEMO (when multiple MRs are connected together). Integrating the MANET and the NEMO (MANEMO) provides the necessary additions to the existing protocols (IPv6, neighbor discovery (ND), and NEMO) to support the nested MRs. It provides a mechanism to select the most suitable path to the Exit Router (ER) as a default in the MANEMO Fringe Stub (MFS). The NCM (NEMO centric MANEMO) protocol is introduced to address the nested NEMO issues (e.g. pinball problem) by using the MANET routing a protocol (i.e., OLSR), while the MCM (MANET centric MANEMO) protocol is introduced to address the MANET problem (e.g. Internet connectivity). The main aim of this paper is to investigate the current approaches that are introduced to provide the route optimization (RO) for the NEMO. It highlights the strengths and the limitations of these approaches. Both the qualitative and the quantitative evolutions of these proposals are hereby presented.  相似文献   

18.
基于移动AdHoc网络环境中的节点能量消耗速度,提出一种新的网格路由协议。定义一个计算节点能量消耗速度的函数,以该函数值为路由参数,结合Floyed算法进行最优路径选择。与原有协议的比较结果表明,该协议可以降低节点能耗,延长网络生命周期。  相似文献   

19.
在采用无线自组网按需平面距离矢量(AODV)路由协议的移动自组网(MANET)网关设计中,针对MANET节点的微移动特性,提出应用于MANET路由子层的微移动管理策略,并在AODV路由协议中进行实现。在NS2平台上的仿真结果表明,采用微移动管理策略的MANET网关可有效降低MANET网络访问Internet的时延,并能减少MANET内控制报文的开销。  相似文献   

20.
MANET路由协议一直是国内外学者的研究热点,但仿真验证却影响了科研工作者研究的进度。引入一种新的网络仿真平台J-Sim。在J-Sim下,对MANET中具有代表性的两种路由协议(AODV、GPSR)进行性能仿真,实验结果表明J-Sim可以真实的仿真MANET的运行,获取有价值的仿真结果。  相似文献   

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