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1.
2.
提出的MWA_MCP(maximal weight amputation for multi-constrained problem)算法,充分利用了BFS(bread first search)算法计算复杂度简单的特点,使用BFS搜索QoS路径.MWA_MCP在搜索过程中有选择地去掉QoS性能差的边,即权重较大的边将在搜索中有策略地被去掉.与仿真的几个算法相比,MWA_MCP体现了较高的路由性能.  相似文献   

3.
IP multicast routing through ATM networks   总被引:1,自引:0,他引:1  
The purpose of this paper is to have a closer look at the ‘core’ technology providing interworking between connectionless TCP/IP internetworks and switched ATM networks. The scope of the paper is IP multicast, while the main focus is on the network side of multicast, more precisely, on layers three and two of Internet architecture dealing with IP multicast routing. The paper analyses both practically available solutions and those being currently under discussion in IETF as Internet drafts. As a background of this comparison, the possible convergence of IP and ATM multicast service models is discussed. Major conclusions, based on simulation studies and scalability analysis are: (i) the high mapping overhead requires a separate address resolution service for unicast and multicast addresses; and (ii) efficient convergence has to make obsolete classical IP over ATM (M. Laubach, Classical IP and ARP over ATM, Network Working Group, Request for Comments: 1577, Category: Standards Track, January, 1994 [1]) in order to permit ‘cut-through’ within the ATM domain.  相似文献   

4.
《Computer Communications》2001,24(3-4):416-421
This paper presents a planned routing algorithm (PRA) and a hierarchical routing algorithm (HRA) for ATM networks. The PRA can establish the multicast tree with the presence of bandwidth and delay constraints. The HRA can be compliant with the PNNI specification from the ATM Forum. It uses an adaptive and iterative path search approach and takes advantage of the PNNI hierarchical network structure to reduce path computation complexity and maximize network throughput. The performances of the PRA and HRA are evaluated by simulations. The simulation results show that the PRA can provide the best performance while the complexity is acceptable and the HRA can reduce processing time and improve network utilization, and both are suited for QoS requirements of ATM networks’ routing.  相似文献   

5.
Satellite network users want to unify different satellites to enhance the quality-of-service (QoS) stability of the satellite networks and select feasible paths through different networks to feed different applications. Unfortunately, the state of affairs is that different applications need to use several different application programming interfaces and to design different protocols on how and when to use a specific network. This is troublesome and error-prone as the application programming interfaces vary a lot. In this paper, we design a Virtual Strategy in satellite network based on which a QoS routing service scheme is then proposed. We analyze why applications should use and benefit from Virtual Strategy. This Virtual Strategy is a middleware solution that enables seamless usage of services from different satellite network parts. And then, the supporting QoS routing solution enables the committed QoS services over Virtual Strategy. Finally, we provide a comparison between the previous satellite networks and our work. The simulation results show that our Virtual Strategy QoS routing scheme demonstrates dominated performances under complex architecture.  相似文献   

6.
Congestion control based dynamic routing in ATM networks   总被引:2,自引:0,他引:2  
In this paper we describe briefly a dynamic multi-path algorithm that has been considered for connection oriented asynchronous transfer mode (ATM) networks. Our scheme takes advantage of a cell multiplexing capability that has particular advantage in networks supporting variable bit rate (VBR) traffic. The fundamental objective of the scheme is to propose a congestion control based scheme that bridges the gap between routing and congestion control as the network becomes congested. The proposed routing scheme works as a shortest path first algorithm under light traffic conditions. However, as the shortest path becomes congested under unbalanced heavy traffic, the source uses multiple paths when and if available to distribute the calls and reduce cell loss. This mechanism will provide good Quality of Service for clients within the given constraints. We compare the performance of the proposed scheme with other competitive schemes. The throughput and cell loss performance are compared via simulations. These have been carried out concentrating on a five node network, each with varying traffic patterns, with the intention of gaining insight into the strengths and weaknesses of the various schemes.  相似文献   

7.
The technical development drives the future networks to become large-scale, heterogeneous, and dynamic. Bio-inspired networking can help reduce the time-space complexity of the complex network. Due to the good features such as self-organization and self-management, self-organizing network (SON) will most probably be a priority choice for the next generation network. In this paper, a swarm intelligence based Quality of Service (QoS) routing protocol is proposed for SON. The inaccurate routing and QoS information is described with fuzzy mathematics whilst the utilities of both the user and the network service provider are considered by applying game theory. Based on the multi-robot navigation algorithm, the protocol is able to search a routing path which can satisfy the user QoS requirements and achieve the Pareto optimal utilities of the user and the network service provider under Nash equilibrium. The proposed protocol is implemented and evaluated by extensive simulation experiments. The results show that it beats both other swarm intelligence based routing protocols and the traditional Dijkstra algorithm based routing protocol. The searched routing paths support the win–win effect for both the user and the network service provider.  相似文献   

8.
王学毅  沈曦 《计算机应用研究》2009,26(11):4263-4265
讨论了基于神经网络自学习算法实现QoS路由决策的问题。为了证明利用人工神经网络优化路由决策的可行性,在由17台服务器(节点)搭建的实验网络环境中,每个节点上均设计了由几个神经元组成的神经网络,各神经元依据网络的测量数据,通过学习算法动态地进行路由决策。实验结果表明,在以最小跳转数或最小延时为QoS目标时,神经网络所提供的路由决策均可以有效地使QoS接近最优值;同时,当神经网络综合考虑延时和最小跳转数两项QoS指标时,网络延时状况要优于只考虑一项指标的情况。实验结果证明了利用神经网络在节点上进行分布式的路由  相似文献   

9.
6LoWPAN中分层路由协议HiLow的改进   总被引:1,自引:0,他引:1       下载免费PDF全文
6LoWPAN标准将下一代互联网协议IPv6与IEEE 802.15.4标准联系起来,使得在低速无线个人区域网络(LoWPAN)上进行基于IPv6的数据传输成为可能。HiLow作为一种基于Mesh-under原理的分层路由方式,大大减少了控制报文的数量及存储空间的需求。通过对HiLow的父节点选择策略及路由恢复策略进行改进,增强了6LoWPAN网络的稳定性及路由的可靠性。最后在NS2中通过仿真实验对所做改进进行了验证,结果显示当存在失效节点时改进后的协议仍能保持较高的转发成功率。  相似文献   

10.
无线传感器网络QoS路由研究进展*   总被引:1,自引:0,他引:1  
传统网络中的服务质量(quality of service,QoS)路由协议很难直接有效地应用到无线传感器网络中,因此人们针对无线传感器网络提出了一些新的QoS路由协议。首先探讨了无线传感器网络中QoS路由协议的一些特点,分析了设计QoS路由协议所面临的挑战;然后着重分析了当前提出的一些QoS路由协议的QoS机制、特点以及优缺点,并对这些路由协议进行了分类和比较;最后总结了QoS路由协议未来的研究策略和发展趋势。  相似文献   

11.
无线传感器网络QoS路由寻优问题是NP类问题,在寻找最优路径时,除了要满足时延、抖动、丢包率等约束条件,还要考虑路径的能量均衡。采用优化的蚁群算法求解该问题,将这些约束条件综合为适应度函数的参数,通过计算适应度值,找到最优路径。仿真结果表明,算法具有较快的收敛速度,能够搜索到时延最小和能量较均衡的路径,并尽量避免陷入局部最优解。  相似文献   

12.
无线多媒体传感器网络QoS路由算法研究   总被引:2,自引:0,他引:2  
由于廉价的CMOS摄像头、麦克风的出现,以及对含有丰富信息的图像,视频和音频信息需求导致了无线多媒体传感器网络-(WMSN)的出现.WMSN具有资源有限、可变的信道容量、数据高度冗余等特点,使得WMSN的QoS路由具有极大的挑战性.提出了一种基于Mesh结构的WMSN,并在该结构体系下,提出了一种基于蚁群算法的QoS路由算法.实验研究表明,蚁群算法具有不依赖全局信息的优点,具有应用于WMSN的前景.实验同时表明,决定蚁群算法收敛速度以及会影响传感器网络性能的一些关键参数较难确定,需要进一步研究.  相似文献   

13.
基于遗传算法的无线网状网QoS多播路由算法   总被引:1,自引:1,他引:0  
探讨了基于遗传算法的无线网状网QoS多播路由算法,选用边集表示方式对多播树进行编码,其空间复杂度为O(N),给出了该编码方式下的初始种群生成算法RandWalkMT,同时对传统的遗传操作进行改进使子代个体中不会产生非法多播树,从而避免了复杂的惩罚机制或多播树修复算法。实验表明该算法收敛快且性能较好。  相似文献   

14.
基于熵权系数法的无线传感器网络自适应QoS路由算法   总被引:1,自引:0,他引:1  
针对无线传感器网络中不同业务对服务质量(QoS)指标的不同要求,以及QoS指标在网络运行过程中实时变化的特点,提出一种基于熵权系数法的自适应QoS路由(EAQR)算法。算法将路由建立过程抽象成多指标加权评分的问题,选取节点负载、平均能量势、通信时延作为QoS评价指标,采用熵权系数法自适应地确定指标的权重,选择最优节点转发数据。仿真实验显示,与有序分配路由(SAR)、能量感知QoS路由(EQR)算法相比,EAQR算法可以有效降低网络平均端到端延迟,减少丢包率,延长网络寿命。  相似文献   

15.
The relentless growth of Internet, which has resulted in the increase of routing table sizes, requires consideration and new direction to address Internet scalability and resiliency. A possible direction is to move away from the flat legacy Internet routing to hierarchical routing, and introduce two-level hierarchical routing between edge networks and across transit networks. In this way, there is also an opportunity to separate the routing locator from the terminal identifier, to better manage IP mobility and mitigate important routing security issues. In this paper, we study the extended traffic engineering capabilities arising in a transit-edge hierarchical routing, focusing on those multi-homed edge networks (e.g., Cloud/content providers) that aim at increasing their Internet resiliency experience. We model the interaction between distant independent edge networks exchanging large traffic volumes using game theory, with the goal of seeking efficient edge-to-edge load-balancing solutions. The proposed traffic engineering framework relies on a non-cooperative potential game, built upon locator and path ranking costs, that indicates efficient equilibrium solution for the edge-to-edge load-balancing coordination problem. Simulations on real instances show that in comparison to the available standard protocols such as BGP and LISP, we can achieve a much higher degree of resiliency and stability.1  相似文献   

16.
已经提出的一些基于复制的路由协议,如传染路由,不能以低代价实现高成功率.对车辆网络中设计了一种有效的基于复制的路由协议ARR.ARR是一种完全分布式协议,它包含两个设计目标:a)在消息生存期内将绝大多数消息成功发送;b)尽可能产生较低的发送代价.为了以低代价实现高成功率,ARR对一条消息的拷贝数量采取自适应策略.另外,为分配消息拷贝提出了两种分配方法.基于真实车辆行驶数据的仿真实验表明,相比其他四种路由协议,ARR以较低的发送代价实现了较高的发送成功率.  相似文献   

17.
能量有效的无线传感器网络层次型路由协议   总被引:2,自引:1,他引:2       下载免费PDF全文
为改善LEACH中节点能耗不均而过早失效的情况,提出了一种能量有效的无线传感器网络层次型路由协议EEHRP,它采用一种智能延迟策略选取簇头,尽可能使得剩余能量越高的节点时延越小,它们能够先于周围剩余能量较低的节点发送簇头通告。在路由算法中引入了网关节点,能有效避免簇头远距离传送数据造成的能耗过多。仿真表明,EEHRP可使节点的能量消耗更均匀,有效地延长了网络生存时间。  相似文献   

18.
Mobile ad hoc networks (MANETs) follow a unique organizational and behavioral logic. MANETs’ characteristics such as their dynamic topology coupled with the characteristics of the wireless communication medium make Quality of Service provisioning a difficult challenge. This paper presents a new approach based on a mobile routing backbone for supporting Quality of Service (QoS) in MANETs. In real-life MANETs, nodes will possess different communication capabilities and processing characteristics. Hence, we aim to identify those nodes whose capabilities and characteristics will enable them to take part in the mobile routing backbone and efficiently participate in the routing process. Moreover, the route discovery mechanism we developed for the mobile routing backbone dynamically distributes traffic within the network according to current network traffic levels and nodes’ processing loads. Simulation results show that our solution improves network throughput and packet delivery ratio by directing traffic through lowly congested regions of the network that are rich in resources. Moreover, our protocol incurs lower communication overheads than AODV (ad hoc on-demand distance vector routing protocol) when searching for routes in the network.  相似文献   

19.
一种节能的无线传感器网络QoS路由算法   总被引:1,自引:0,他引:1  
针对无线传感器网络中不同业务对QoS的不同要求,提出了一种新的QoS路由算法—EBQoS算法。算法通过记录邻居节点到Sink节点的最小跳数信息建立到Sink节点的多条路径,并根据信息包的QoS要求和节点剩余能量选择合适的路径进行路由。通过仿真实验与顺序分配路由(SAR)算法的比较,结果表明该路由算法在提供差别服务和提高网络生存期方面具有明显的优势。  相似文献   

20.
针对无线传感器网络中不同业务对服务质量(QoS)的不同需求,提出一种基于离散粒子群优化(DPSO)的无线传感器网络QoS路由(DPSO-QR)算法。算法将路由建立过程抽象为多目标优化过程,以节点间通信的传播损耗、时延、带宽、丢包率为优化目标,利用DPSO算法实现多目标优化,为拥有不同QoS需求的网络业务提供满足其特有需求的优化路由。仿真实验表明:与SAR,EQR算法相比,DPSO-QR算法降低了网络平均端到端时延,减小了丢包率,延长了网络寿命。  相似文献   

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