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1.
Ad Hoc网络中的QoS(Quality of Service)保障已成为一个研究热点,论文针对Ad Hoc网络中的QoS路由问题进行了研究。目前大多数的Ad Hoc路由协议只支持一个QoS参数,不能满足实际的需要。多参数的QoS路由是典型的NP难度问题,难以用普通方法解决。论文引入了量子遗传算法来解决此问题,提出了一种支持多QoS参数的Ad Hoc路由协议。仿真实验表明,该协议具有良好的性能,能够有效地解决多QoS约束的路由问题。  相似文献   

2.
移动自组网中基于路径稳定性的QoS路由协议   总被引:6,自引:0,他引:6  
随着多媒体应用日益普及,在移动自组网中提供QoS已经逐渐成为自组网研究的热点问题,然而现有的自组网QoS路由协议主要集中研究如何找到满足QoS条件的可行路径而没有考虑可行路径的稳定性,针对移动自组网的特点,提出了基于路径稳定性的QoS路由协议PSQRP,该协议基于路径稳定性PSF来选择路由,减少了链路断开的概率,同时协议采用了主次预约技术来预约网络资源,进一步提高了协议的请求成功率,模拟结果表明,在动态的网络环境下,PSQRP协议能够取得良好的性能。  相似文献   

3.
为更好地将移动自组网络用于网络控制系统(NCS),结合NCS的网络特性,提出了一种基于链路信号质量的QoS路由算法。主要QoS机制包括根据接收信号强度选择较稳定的路由;用Hello报文广播节点的预留带宽;中间节点为所有受影响的数据流修复路由、目的节点向源节点广播路由修复报文进行路由修复。NS2仿真表明当节点移动性强时,该QoS路由算法可有效减少网络的平均端到端时延和丢包率,提高控制系统稳定性。  相似文献   

4.
A mobile ad hoc network (MANET) is a collection of mobile hosts that form a temporary network on the fly without using any fixed infrastructure. Recently, the explosive growth in the use of real-time applications on mobile devices has resulted in new challenges to the design of protocols for MANETs. Chief among these challenges to enable real-time applications for MANETs is incorporating support for quality of service (QoS), such as bandwidth constraints. However, MANETs having a high ratio of topology change make routing especially unstable; making stability is an important challenge, especially for routing having a quality of service provision. In this paper, we propose a reliable multi-path QoS routing (RMQR) protocol with a slot assignment scheme. In this scheme, we examine the QoS routing problem associated with searching for a reliable multi-path (or uni-path) QoS route from a source node to a destination node in a MANET. This route must also satisfy certain bandwidth requirements. We determine the route expiration time between two connected mobile nodes using global positioning system (GPS). Then, two parameters, the route expiration time and the number of hops, are used to select a routing path with low latency and high stability. Simulation results show that the proposed RMQR protocol have some outstanding properties when compared with Lin's [Lin C-R. On-demand QoS routing in multihop mobile networks. In: Proceedings of the twentieth annual joint conference of the IEEE computer and communications societies (INFOCOM), vol. 3(22–26), 2001, p. 1735–44], Liao's [Liao W-H, Tseng Y-C, Wang S-L, Sheu J-P. A multi-path QoS routing protocol in a wireless mobile Ad Hoc network. Telecommunication Systems 2002;19(3–4):329–47], and Chen's [Chen Y-S, Tseng Y-C, Sheu J-P, Kuo P-H. An on-demand, link-state, multi-path QoS routing in a wireless mobile Ad-Hoc network. Computer Communications 204;27(1):27–40] protocols.  相似文献   

5.
针对无线传感器网络中不同应用的QoS需求,提出了一种路由协议QMR。该协议使用节点剩余能量、可用缓存以及信道质量等度量值综合评估路径传输可靠性,根据量化的评估值构建自源节点至目的节点的多条路径;并引入路径选取模型,允许数据包依据优先级同时在多条路径上传输;接着采用按通信量更新策略,根据网络流量情况动态调整路由更新频率。通过仿真实验分析得出,该协议在降低网络能耗、提供差别服务方面具有良好的性能。  相似文献   

6.
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   

7.
ABSTRACT

Security is an essential service for mobile network communications. Routing plays an important role in the security of mobile ad-hoc networks (MANETs). A wide variety of attacks targets the weakness of MANETs. By attacking the routing protocols, attackers can absorb network traffic, injecting themselves into the path between the source and destination. The black hole attack is one of the routing attacks where a malicious node advertise itself as having the shortest path to all nodes in the network by sending fake route reply. In this paper, a defense scheme for detecting black hole node is proposed. The detection is based on the timing information and destination sequence numbers maintained in the Neighborhood Route Monitoring Table. The table maintains the record of time of Reply. A black hole node will send a route reply message without checking the routing table as the legitimate node normally does. This reduced reply time is used to detect the black hole node. To improve the security further, the destination sequence number is checked with the threshold value, which is dynamically updated. The simulation results demonstrate that the protocol not only detects black hole attack but also improves the overall performance.  相似文献   

8.
Routing algorithms play a critical role in meeting both the stringent quality of service (QoS) requirements of guaranteed services and the certain QoS requirement of assured services over next-generation multiservice high-speed networks. In this paper, we propose the use of optimal least weight routing (OLWR) algorithm for routing QoS flows in high-speed networks. The main principle of our algorithm is that the choice of the most appropriate route is based on a set of parameters (least weight parameters) that estimate and consider the impact that the acceptance and routing decision of a call request belonging to a specific class would have on the network and other classes of service. Effective bandwidth, bandwidth and trunk reservation techniques, along with load balancing and packing trade-off considerations, are also introduced in the proposed routing algorithm. The performance evaluation of our algorithm is achieved via modeling and simulation of multiclass service routing in various network topologies. The performance results demonstrated that OLWR outperforms both the multihop least-loaded routing algorithms and the multihop most-loaded routing algorithms in terms of both revenue and carried load.  相似文献   

9.
卫星网络基于信任的认证路由协议   总被引:1,自引:0,他引:1  
安全路由协议是保障卫星网络安全运行的一个重要因素。针对现有卫星网络路由大多缺少安全机制的问题,运用基于椭圆曲线的签名方案保证路由报文的合法性,通过改进的信任评估机制排除内部恶意节点参加选路,设计了适用于高空通信平台(HAP)/低轨道(LEO)结构的层次式安全路由协议。分析表明该协议能够抵御多种常见的路由攻击。  相似文献   

10.
In mobile ad hoc network (MANET), on-demand routing protocols are proposed for establishing a route in a distributed manner only when a source host originates a data packet addressed to the destination host. In source-based routing (SBR) protocols, route discovery usually raises a large number of request packets for exploring the current state of the network, but it also performs the collection of useful information for future routing decisions. How to store and manage this collected information in the limited size of cache in order to improve routing performance is still an open issue in the development of an SBR scheme. This paper proposes a novel hash caching mechanism and distributed hashing routing methods to store, utilize, and manage the cached routes in order to improve cache capacity, routing performance, and network throughput. The experimental results indicate that the proposed mechanism offers high cache capacity, efficient route discovery, and good throughput for the MANET.  相似文献   

11.
一个ad hoc网络是一个多跳无线网络,网络中的节点互相通信而不依赖于预先架设的固定基础设施,选路协议中的频繁的路由失败和高控制开销致使系统性能降低.本文提出了一个稳定的分布式Ad hoc路由协议,该协议支持QoS选路用于多媒体应用.  相似文献   

12.
针对无线网格网络(wireless mesh network, WMN)中传统路由协议重复传输且频繁运行路由发现过程的问题,提出了基于期望传输次数(expected transmission count, EXT)路由度量的协调机会路由协议。首先,利用无线网络的广播特性寻找拥有最大化吞吐量和最小丢包率的最优路由协议;然后,使用ETX路由度量标记关键问题的计算成本;最后,利用源节点发送的信用和区域成本计算节点的区域,并实现路由发现。仿真结果表明,提出的路由协议在不同参数情况下,平均吞吐量可提高32%,投递率可由10%提高至20%,相比其他几种较新的路由协议,提出的协议在吞吐量、投递率和平均端与端间延迟方面具有更好的性能。  相似文献   

13.
As the use of mobile devices continues to rise, trust administration will significantly improve security in routing the guaranteed quality of service (QoS) supply in Mobile Ad Hoc Networks (MANET) due to the mobility of the nodes. There is no continuance of network communication between nodes in a delay-tolerant network (DTN). DTN is designed to complete recurring connections between nodes. This approach proposes a dynamic source routing protocol (DSR) based on a feed-forward neural network (FFNN) and energy-based random repetition trust calculation in DTN. If another node is looking for a node that swerved off of its path in this situation, routing will fail since it won’t recognize it. However, in the suggested strategy, nodes do not stray from their pathways for routing. It is only likely that the message will reach the destination node if the nodes encounter their destination or an appropriate transitional node on their default mobility route, based on their pattern of mobility. The EBRRTC-DTN algorithm (Energy based random repeat trust computation) is based on the time that has passed since nodes last encountered the destination node. Compared to other existing techniques, simulation results show that this process makes the best decision and expertly determines the best and most appropriate route to send messages to the destination node, which improves routing performance, increases the number of delivered messages, and decreases delivery delay. Therefore, the suggested method is better at providing better QoS (Quality of Service) and increasing network lifetime, tolerating network system latency.  相似文献   

14.
在确保大规模无线传感器网络信息可靠传输的前提下,尽可能降低网络能量开销,提出了大规模无线传感器网络的自适应节能路由算法。针对长江三峡库区水质监测的具体应用环境,构建了网络模型,采用梯度型拓扑生成器生成网络拓扑,利用可以平衡负载的节能自适应算法进行最优路由选择,建立了应用于大规模无线传感器网络的自适应节能路由算法。在具有代表性的两种不同网络环境中,对该算法的节能效果进行测试,结果表明了算法的可行性和先进性;该算法能有效地将网络负载平均分配于整个网络中,减少网络的整体能量开销,延长整体网络的寿命。  相似文献   

15.
针对当前SDN架构存在路由算法复杂度高、QoS流满意度低和单链路故障等问题,提出了一种基于软件定义网络的多约束QoS双路径路由优化算法(SDN_MCQDP)。利用控制器获得全局网络状态信息,生成基于目的节点的有向无环图。在多约束QoS路由选择阶段,通过拉格朗日松弛对偶算法将多约束问题转化为线性规划问题。使用反向链路删减得到满足多约束QoS的节点不相交的双路径冗余链路,使链路故障后的数据传输得到保障。从路由计算时间、链路利用率、QoS流满意度等方面对算法进行仿真实验。结果表明,与MODLARAC、QT、RMCDP_RD、H_MCOP算法比较,SDN_MCQDP能够有效降低传输时延,减少路由计算时间,提高链路利用率,且在链路发生故障后仍能满足QoS需求。  相似文献   

16.
Ad Hoc网络中基于能源节省的单向QoS路由协议   总被引:1,自引:0,他引:1       下载免费PDF全文
邓曙光  胡赛纯  杨冰 《计算机工程》2006,32(24):118-120
针对阿ad hoc网络中节点能源受限,隐藏终端和QoS需求等问题,提出了一种基于能源节省的单向QoS路由协议。该协议利用网络中存在的单向链路,采用QoS策略,通过在最短路由集中选取能源较多的路径承担较多传输任务以延长网络生存时间。仿真结果表明,该协议比相关路由算法具有更好的网络性能,能有效支持单向ad hoc网络中具有QoS需求的信息传输。  相似文献   

17.
自组网QoS路由协议综述   总被引:10,自引:0,他引:10  
郑锋  李腊元  高晔方  连进 《计算机应用》2006,26(2):270-0272
自组网是一组带有无线收发装置的移动节点组成的一个多跳的临时性的自治系统。随着网络的发展和用户需求的不断提高,自组网的服务质量(QoS)问题已成为当前研究的热点。综述了自组网QoS路由协议研究方面的一些最新进展,并对该研究所提出的主要QoS路由协议进行分析、对比,有助于QoS路由协议的进一步研究。  相似文献   

18.
传统分布式的网络架构制约路由算法的创新,软件定义网络的出现为路由算法的优化提供了新思路。已有研究中,启发式算法广泛应用于服务质量路由,但由于计算复杂度高而无法在大型网络中应用。而其他算法均存在不同程度的问题,要么复杂度较高,要么算法性能较差,如最短路径算法。基于 SDN 分级分域架构,提出了 LC-LD 路由算法,综合时延条件和代价度量约束并在计算复杂度和算法性能之间保持平衡。仿真分析表明,LC-LD路由算法在有较低的计算复杂度的同时还有较高的服务质量路由选路性能。  相似文献   

19.
自组网环境下基于QoS的路由协议   总被引:21,自引:0,他引:21  
英春  史美林 《计算机学报》2001,24(10):1026-1033
自组网是一组带有无线收发装置的移动节点组成的一个多跳的临时性的自治系统。在这种环境中,由于节点无线通信覆盖范围的有限性,需要借助其它中间节点进行分组转发到达信宿。常规路由协议在自组网环境无法有效地正常运行。文中首先描述了自组网的概念和特点,在此基础上提出了自组网环境下的基于QoS的路由协议。该路由协议的主要思想是根据无线链路两个重要指标:平均错误分组率和生存时间进行路由发现、选择和维护。相对于跳数而言,它们向用户提供了最有可能满足特定QoS需求的信息流的传输。  相似文献   

20.
Wireless mesh networks can provide low-cost solutions for extending the reach of wireless access points by using multi-hop routing over a set of stationary wireless routers. The routing protocol for these networks may need to address quality considerations to meet the requirements of the user. In this paper, we present a quality based routing protocol for wireless mesh networks that tries to maximize the probability of successful transmissions while minimizing the end-to-end delay. The proposed routing protocol uses reactive route discoveries to collect key parameters from candidate routes to estimate the probability of success and delay of data packets transmitted over them. To achieve accurate route quality assessments, a new route quality metric is proposed that uses performance models of data packet transmissions as opposed to estimating route quality from the transmission of control packets, which have different transmission characteristics. These models are developed after careful evaluations of multi-hop wireless transmissions and validated by computer simulations. Relevant parameters that can be used to assess the route quality metric using these models are explained. Extensive performance evaluations of the proposed quality based routing protocol are presented and its benefits in comparison to some other known routing protocols are discussed.  相似文献   

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