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1.
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   

2.
ZigBee结合GPRS的无线自组网的数据传输系统   总被引:2,自引:0,他引:2  
为解决数据通过无线自组网远距离传输所存在的问题,设计了ZigBee结合GPRS的数据传输系统。介绍了系统的硬件架构以及终端通过路由转发数据的过程,同时对终端节点发送、路由转发及数据上报到网关等环节进行了软件设计;最后对系统运行进行了测试。测试结果显示,数据可以稳定地从终端节点传输到服务器端,系统有效地实现了数据在无线自组网中的远程传输。  相似文献   

3.
为了提高机车近距离无线重联控制系统的冗余性和抗干扰性,文章基于自组网技术设计了一套机车近距离无线重联控制系统,其通过建立无线通道传输WTB总线数据、关键硬线信号及语音信号,实现了多台机车同步控制运行.该系统利用自组网技术自愈合的特点,可以在不增加设备的前提下,进一步提高机车近距离无线重联控制系统的冗余性;同时通过自动跳...  相似文献   

4.
基于MCU控制各种功能模块,制作了一种利用3G及微功耗自组网进行图像传输、信息采集、远程控制的系统.该系统可以利用INTERNET、3G、无线WIFI自组网监控现场或采集数据,且可以通过电力线载波对电气设备进行控制.各个系统均采用模块化设计,短时间内可根据需要组建一个新系统,介绍了该系统的组成及工作流程.  相似文献   

5.
在无线自组织网(Ad hoc Network)中使用头压缩算法可以极大的提高语音业务在自组网中的传输效率.本文首先介绍了适用于自组网的IP/UDP/RTP头压缩算法然后在分析了Ad hoc 网测试床数据处理流程的基础上,对测试床的数据处理流程进行了修改,在中间层驱动中实现了该头压缩算法;最后通过比较,分析了头压缩算法的实时话音业务传输性能.  相似文献   

6.
韩春燕  陈渝  易发胜 《计算机工程》2008,34(11):123-125
分析无线自组网中关于传输控制协议(TCP)的问题,研究基于按需确认的TCP协议在无线自组网中的改进算法。该算法规定接收方须根据发送方的要求对数据报文进行确认,减少确认(ACK)数量并消除延迟ACK对TCP传输效率的影响,提高了无线自组网中TCP的性能。仿真试验结果证明了该算法的有效性。  相似文献   

7.
在蚂蚁算法基本规则的启发下,基于移动Agent的分布式路由算法研究(AntNet)的基础上,设计出一种新的基于蚁群代理优化的无线自组网多路径优化的路由协议算法(AdHoc-AntNet).这是一种新的无线自组网的路由算法,其结合蚁群理论和无线自组网本身的特点,对AntNet进行了改进,从而建立更有效的、适合无线自组网的路由协议算法.通过仿真试验表明,与AODV相比该协议在路由开销、平均分组延迟和吞吐量等方面都有明显的改进.  相似文献   

8.
如何安全地在无线自组网上传输数据信息,鉴别数据信息来源的真实性,确保信息的完整性和不可抵赖性成为近年来相关研究的热点.为有效地提高无线网络的安全性,对传输内容进行加密及其身份认证成为关键技术.本文在对无线自组网以及ECC算法特点进行分析的基础上,采用AES算法对音频信号加密,ECC私钥实现对AES密钥的加密,在接收方实现对音频信号的解密和模式认识,从而达到对发送方身份认证的目的,较好得解决了无线自组网环境下的身份认证问题.  相似文献   

9.
针对470 MHz~510 MHz频段内越来越广泛的低功耗、低成本的无线集中采集系统应用.该文设计了一种基于ARM Cortex-M0微控制器,具有实现自组网,自动路由,节点自动跳频功能的无线终端模块.详细介绍了系统的主要结构,模块的硬件和软件设计,详细阐述了自组网和自动路由的原理和实现方法.设计中实现了自组网、自动路由、自动绑定地址等功能.应用证明,该系统可以应用在无线抄表、安防、智能家居、无线传感器网络等多种中短距离系统中,性价比高,稳定可靠.  相似文献   

10.
网络仿真在自组网开发过程中评估新的协议性能的基本技术, 该文介绍了网络建模问题,比较了各种传统路由算法和自组网算法.讨论了自组网的确定性和不确定性建模,分析了NS、OPNET和MATLAB等几种仿真工具.基于不确定建模原理,使用MATLAB和C设计并实现了一个无线自组网路由仿真器.  相似文献   

11.
人们一般只基于2kbps发送速率下研究移动自组网中路由协议的性能,基于对多媒体业务的支持,该文在144kbps发送速率下研究了,移动自组网中路由协议AODV(Ad Hoc按需距离矢量路由)的性能,并与2kbps发送速率下的性能进行了比较分析。研究结果表明,与2kbps发送速率下相比,144kbps发送速率的报文投递率要高,同时平均端到端的时延、路由负荷、MAC负荷也高。  相似文献   

12.
基于QoS路由及保障路由实施是支持MANET应用的关键.为解决MANET中QoS问题,在移动预测机制下提出了一种基于QoS保障的组播协议.该协议通过簇头选举,移动预测和QoS控制策略在组播源与含目的节点的组播簇头间确定最稳传输路径,并采用基于动态资源管理的QoS路由模型来保障路由实施.仿真结果显示该方案可获得较高传输成功率和较低控制开销,能有效支持MANET中具有QoS需求的组播传输.  相似文献   

13.
为了提高自组网的性能并满足多媒体数据传输等应用的需要,提出了一种基于AODV协议的QoS延伸及优化算法。该算法以AODV为基础,采用限制路由请求分组转发的机制并获取稳定的路由,并满足QoS约束条件。仿真实验结果表明,该算法降低了网络负载,减少了开销和提高了数据包传输成功率。  相似文献   

14.
研究了在3G网络数据传输速率下路由协议AODV(AdHoc按需距离矢量路由)的性能。模拟结果分析了不同数据传输速率下报文丢失率、路由发现频率、端到端的时延,结果表明随着通信节点移动速率的增加此三项指标值都变大。模拟结果为移动自组网与3G网络的结合提供了参考。  相似文献   

15.
刘明艳  乔良  刘庆宏 《计算机工程与设计》2007,28(7):1572-1574,1670
TCP协议最初是为有线网络设计,它假设数据包的丢失都是由网络拥塞引起.但在MANET中,链路的高误码率和节点移动等都会引起数据包的丢失.如果不加改进地把传统TCP应用于MANET中,它会把非拥塞因素引起的数据包丢失也当作是网络拥塞,从而错误的触发拥塞控制,导致传输性能的下降.首先讨论了MANET中影响TCP性能的主要因素;然后从传输层、网络层和链路层3个层面,分别介绍了提高MANET中TCP性能方法的工作机制;并对这些方法进行了分析比较.最后指出了今后的工作方向.  相似文献   

16.
Mobile Ad-hoc NETworks (MANET) are infrastructureless networks where self-configuring mobile nodes are connected by wireless links. Because of its decentralized operation, these nodes rely on each other to store and forward packets. Video transmission over MANETs is more challenging than over conventional wireless networks due to rapid topology changes and lack of central administration. Most of the proposed MANET protocols assume that all nodes are working within a cooperative and friendly network context. However, misbehaving nodes that exhibit abnormal behaviors can disrupt the network operation and affect the network availability by refusing to cooperate to route packets due to their selfish or malicious behavior. In this paper, we examine the effect of packet dropping attacks on video transmission over MANETs. We also study the effects of mitigation using intrusion detection systems to MANET in presence of video traffic. To the best of our knowledge, this is the first attempt to study multimedia over such environments. We propose a novel intrusion detection system, which is an adaptive acknowledgment scheme (AACK) with the ability to detect misbehaved nodes and avoid them in other transmissions. The aim of AACK scheme is to overcome watchdog weaknesses due to collisions and limited transmission power and also to improve TWOACK scheme. To demonstrate the performance of our proposed scheme, simulation experiments are performed. The results of our experiments show that MPEG4 is more suitable for our simulation environment than H264 video traffic. The simulation results show that AACK scheme provides better network performance with less overhead than other schemes; it also shows that AACK outperforms both TWOACK and watchdog in video transmission applications in the presence of misbehaving nodes.  相似文献   

17.
在MANET中,节点移动对端到端性能产生消极影响。为了量化此影响,结合链路可用度的概念,将分组发送至下一跳的平均时间作为虚拟时钟节拍,提出一种基于虚拟时钟的MANET性能分析模型。通过此模型可以较准确地求出路径吞吐量和分组平均端到端时延等性能指标,并分析出节点速度、传输半径、分布密度等环境配置参数对这2个陛能指标的影响。  相似文献   

18.
Mobile Ad Hoc Network (MANET) is an infrastructure-less network that is comprised of a set of nodes that move randomly. In MANET, the overall performance is improved through multipath multicast routing to achieve the quality of service (quality of service). In this, different nodes are involved in the information data collection and transmission to the destination nodes in the network. The different nodes are combined and presented to achieve energy-efficient data transmission and classification of the nodes. The route identification and routing are established based on the data broadcast by the network nodes. In transmitting the data packet, evaluating the data delivery ratio is necessary to achieve optimal data transmission in the network. Furthermore, energy consumption and overhead are considered essential factors for the effective data transmission rate and better data delivery rate. In this paper, a Gradient-Based Energy Optimization model (GBEOM) for the route in MANET is proposed to achieve an improved data delivery rate. Initially, the Weighted Multi-objective Cluster-based Spider Monkey Load Balancing (WMC-SMLB) technique is utilized for obtaining energy efficiency and load balancing routing. The WMC algorithm is applied to perform an efficient node clustering process from the considered mobile nodes in MANET. Load balancing efficiency is improved with a higher data delivery ratio and minimum routing overhead based on the residual energy and bandwidth estimation. Next, the Gradient Boosted Multinomial ID3 Classification algorithm is applied to improve the performance of multipath multicast routing in MANET with minimal energy consumption and higher load balancing efficiency. The proposed GBEOM exhibits ∼4% improved performance in MANET routing.  相似文献   

19.
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   

20.
将TCP Veno运行在MANET环境下,采用NS2对其性能进行了仿真测试。仿真结果表明:在存在背景流、有随机丢包并且存在拥塞的MANET网络中,TCP Veno的性能优于TCP Reno,而且在背景流越大,达到拥塞的时间越短、随机丢包越大,TCP Veno的优越性更会非常明显。  相似文献   

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