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QoS multicast routing algorithm based on GA 总被引:9,自引:2,他引:9
1 .INTRODUCTIONTheprovisionofquality of service (QoS) guaranteesisofutmostimportanceforthedevelopmentofthemulticastservices .Multicastroutinghascontinuedtobeaveryimportantresearchissueintheareasofnet worksanddistributedsystems.Ithasattractedtheinterestsof… 相似文献
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Sun Baolin~ & Li Layuan~ . School of Computer Science Technology Wuhan Univ. of Techno logy Wuhan . P. R. China . Dept. of Mathematics Physics Wuhan Univ. of Science Engineering Wuhan . P. R. China 《系统工程与电子技术(英文版)》2006,17(2):417-422
1 .INTRODUCTIONA mobile ad hoc network ( MANET) is a multi-hopwireless network formed by a collection of mobilenodes without the intervention of fixedinfrastructure.Because an Ad hoc network is infrastructure-less andself-organized,it is used to provide i mpromptu com-munication facilities in harsh environments . Typicalapplication areas of mobile ad hoc networkinclude bat-tlefields ,emergency search,rescue sites and data ac-quisitionin remote areas . A mobile Ad hoc networkisalso usef… 相似文献
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Sun Baolin~ & Li Layuan~ . School of Computer Science Technology Wuhan Univ. of Technology Wuhan P. R. China . Dept. of Mathematics Physics Wuhan Univ. of Science Engineering Wuhan P. R. China 《系统工程与电子技术(英文版)》2006,17(3):692-698
1 .INTRODUCTIONMobile ad hoc networks ( MANET) , also calledthe infrastructureless mobile network or self-or-ganized network,consists of a collection of mobilenodes sharing a wireless channel without any cen-tralized control or established communication back-bone .ad hoc networks have no fixed routers ;allnodes are capable of movement and can be connect-ed dynamically in an arbitrary manner . Usually ,these nodes act as both end systems and routers atthe same ti me . Nodes of these netwo… 相似文献
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Yan Xin & Li LayuanDept. of Computer Science Wuhan Univ. of Technology Wuhan P.R. China 《系统工程与电子技术(英文版)》2005,16(4)
1.INTRODUCTION WiththerapiddevelopmentofInternet,mobilenet worksandhigh performancenetworkingtechnology,itbringsoutextensiveinterestsofpeopleinproviding multimediaandreal timeservicessuchasvideoconfer ence,distanceeducation,entertainmentandsoon.Theseservicesrequirecertainquality of service(QoS)fromthenetworks.Thatis,thereshouldbe guaranteesastobandwidth,delay,delay jitter,ratio ofpacket lossandlowcostduringthedatatransmis sion.Meanwhile,multicastserviceshavebeenused invariousmultimediaap… 相似文献
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针对传统卫星网络中业务类型多样化导致的网络配置复杂和业务服务质量(quality of service, QoS)无法得到有效保障的问题,研究了基于软件定义网络(software-defined networking, SDN)的卫星网络架构,提出了一种能够满足多种QoS需求的自适应路由算法。首先,建立了软件定义卫星网络多约束条件路由选择优化模型;然后,使用拉格朗日松弛法对模型进行松弛处理;最后,使用梯度法进行迭代求解,搜索出满足带宽、时延、丢包率等多种QoS的最优路径。研究结果表明,该优化算法在QoS满意度方面相比近地轨道卫星路由算法提高了64%,在时延满意度和丢包率满意度方面相比软件定义路由算法提高了28%。 相似文献
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对于卫星链路参数在复杂空间环境中存在不确定性的问题,研究了一种基于不确定链路参数的卫星网络路由算法。首先,采用三角模糊数描述链路参数的不确定性;在此基础上,建立卫星网络多约束路由模型;然后,设计保证路径有效性的遗传操作,通过遗传算法对路由模型进行求解;最后,通过仿真分析表明,该算法可以在复杂环境中实现高效路由,在平均时延、时延抖动和丢包率等方面有较好的效果。 相似文献
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随着实时组播通信需求的不断增长,要求网络能够提供更加严格高效的QoS(Quality of Service)路由保证,需要设计一个能够同时满足不同QoS约束的高效组播路由算法。此问题可归结为图论中的NP(Non-Polymenital)问题,一般方法是把多个QoS参数加权合并为一单目标函数进行优化。提出了一种基于决策图贝叶斯的多目标QoS组播路由算法,算法在不需做预处理的情况下可对多个不同的QoS参数同时进行优化。仿真结果表明,所提出的算法能够快速收敛于一组满足不同QoS约束的非支配解。 相似文献
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Li Layuan & Li Chunlin Department of Computer Science Wuhan University of Technology Wuhan P. R. China 《系统工程与电子技术(英文版)》2002,13(4)
In recent years, QoS multicast routing has continued to be a very important research topic in the areas of networks. This paper presents a heuristic algorithm for the QoS multicast routing (HAQMR). This heuristic algorithm deals with delay and bandwidth constraints and has low cost. The HAQMR attempts to significantly reduce the overhead for constructing a multicast tree, the proof for correctness of the HAQMR is given, and the performance of the HAQMR is evaluated by simulations. The study shows that HAQMR provides an available approach to QoS multicast routing. 相似文献
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Chen Niansheng~ Li Layuan~ & Dong Wushi~ .School of Computer Science Wuhan Univ. of Technlogy Wuhan R. R. China .Dept.of Computer Science Hubei Normal Univ. Wuhan P. R. China 《系统工程与电子技术(英文版)》2006,17(3):642-647
1 .INTRODUCTIONA mobile Ad hoc network refers to a temporal multi-hop autonomy system,whichis constituted by a groupof mobile nodes containing wireless send-receive equip-ments[1].It possesses manycharacteristics-fast-deploy-able,self-organized,acentric , movable and of multi-hop.It can be wildly applied to many fields ,such asnational defense,emergency and disaster ,scientificin-vestigation and exploration etc .,and uponthat ,it hasgreat prospects[1 ,3 6]. With the wide spread of mo-bile… 相似文献
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Cui Xunxue Gao Wei & Fang Hongyu. New Star Research Institute of Applied Technology Hefei P. R. China . Jiangsu Key Laboratory of Computer Information Processing Technology Soochow University Suzhou P. R. China . Department of Electronic Engineering Information Science University of Science Technology of China Hefei P. R. China . School of Electronic Science Technology Anhui University Hefei P. R. China 《系统工程与电子技术(英文版)》2005,16(2)
1.INTRODUCTION Qualityofservice(QoS)multicastroutinghascon tinuedtobeaveryimportantresearchtopicintheIn ternet.Multicastisacommunicationservicethatal lowssimultaneoustransmissionofthesamemessage fromonesourcetoagroupofdestinationnodes.To carryoutdifferentmulticastsessions,anetworkmust minimizethesessions’resourceconsumption,while meetingtheirrequirements.Efficientallocationof networkresourcestosatisfyQoSrequirementsisthe primarygoalofmulticastrouting.Howevertheinter dependencyandconfli… 相似文献
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卫星网络中由于卫星高动态拓扑和地面用户分布不均,导致卫星网络易出现区域负载失衡。设计高效的动态路由算法是当前卫星网络的研究热点,为此,提出了一种面向双层卫星网络的多业务负载均衡算法。该算法根据卫星链路上的数据传输量进行拥塞判断,根据链路时延因素和链路负载因素进行负载代价计算,不同服务质量(quality of service, QoS)需求的业务进行不同路径选择,通过分流均衡网络流量。仿真结果表明,该算法能够减少数据包的排队时延和丢包率,提高整网吞吐量。 相似文献
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作为下一代高速网络的核心技术之一,多约束服务质量组播路由成为了当前网络研究的重点,但对算法性能进行合理的评价仍是一个开放性问题。提出了一种基于线性能量函数的组播路由算法性能综合评价策略——IESMR。算法通过线性能量函数将待评价组播算法的各项QoS性能转化为单一度量值,考察其距极限最优能量值的偏差半径作为算法性能综合度量指标。 相似文献
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QoS路由是保证网络服务质量的重要组件。但网络状态信息具有固有的不确定性,因此有必要研究不确定信息对QoS路由的影响。通过假设网络带宽和时延的分布符合某种随机变量的特点,分别用概率方法表示出带宽和时延的不确定性,然后求出路径满足给定QoS约束的概率,最后在遗传算法的计算过程中,选择合理的适应度函数,找出满足QoS约束的最大概率解。仿真结果表明该方法能够保证得到满意解的同时缩短搜索时间。 相似文献
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针对由卫星光网络拓扑动态变化、业务多样化和负载不均引起的路由收敛慢和波长利用率低的问题, 提出了一种基于深度强化学习的卫星光网络波长路由分配方法。基于软件定义中轨/低轨(medium earth orbit/low earth orbit, MEO/LEO)双层卫星网络架构, 利用深度强化学习算法动态感知网络当前的业务负载和链路状况, 构造基于时延、波长利用率和丢包率的奖励函数进行选路决策。为了解决单跳链路对整个光路的影响, 引入链路瓶颈因子, 搜索符合服务质量(quality of service, QoS)约束的最优路径。研究结果表明, 与传统卫星网络分布式路由(satellite network distributed routing algorithm, SDRA)算法和Q-routing算法相比, 所提算法降低了网络的时延、丢包率, 提高了波长利用率, 同时也降低了高优先级业务的阻塞率。 相似文献
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1.INTRODUCTION Multicastserviceshavebeenusedbyvariouscontinu ousmediaapplications.Forexample,themulticast backbone(Mbone)oftheInternethasbeenusedto transportrealtimeaudio/videofornews,entertain ment,videoconferencing,anddistancelearning.The provisionofQoSguaranteesisofutmostimportance forthedevelopmentofthemulticastservices.Multi castroutinghascontinuedtobeaveryimportantre searchissueintheareasofnetworksanddistributed systems[1~4].Itattractstheinterestsofmanypeo ple. Afrequently… 相似文献
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路由技术是低轨预警星座通信网络需解决的关键技术之一。设计了低轨预警星座通信网络的拓扑结构。提出了多约束最优路由模型,该模型将链路的时延、切换率和可用带宽转化为传输费用,表示了时延和跳数受限的最小费用路由问题。给出了求多约束最优路由问题的最优解算法,此算法通过缩小可行路径的搜索空间降低计算复杂性。仿真结果表明,该路由算法的复杂性和切换性能优于同类算法,适合于星上在线路由计算。 相似文献
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Traffic engineering has been essential to optimize the utilization of network resource and to provide for QoS,QoS routing is a basic component of traffic engineering in MPLS networks. Aiming at some shortages of certain existing routing algorithms, we propose an efficient bandwidth constrained QoS routing scheme with additional traffic engineering objectives. The objectives of traffic engineering considered in our algorithm are to reduce the blocking probability of requests and to evenly distribute the traffic load. Accordingly, the algorithm avoids using critical links as far as possible by assigning large weights to them as a function of their criticality. The critical links can be specified according to max-flow reduction weight, a new link weight introduced by the algorithm. Then, a new defined additive metric, path saturation,is used to select optimal path. Extensive simulations are carried out to evaluate the performance of the proposed algorithm in terms of call blocking probability and link resource utilization. Compared to other several routing algorithms, the simulation results show the new algorithm performs well. 相似文献
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Zhu Changhua Pei Changxing Li Jiandong Chen Nan & Yi Yunhui State Key Laboratory of Integrated Services Networks Xidian Univ. Xi’an P. R. China 《系统工程与电子技术(英文版)》2006,17(3):685-691
1 .INTRODUCTIONEnd-to-end delay is one of the most i mportantcharacteristics of Internet end-to-end packet dy-namics , which may be applied to QoS manage-ment , SLA management , etc . A better compre-hension of end-to-end delay dynamics can help tosuggest efficient congestion control algorithm andadmission control scheme in which the parametersselection and technical principle can harmonizewith network behaviors . Much work has been doneto end-to-end delay dynamics and various modelshav… 相似文献