简介:ThispaperpresentsadaptivehybridprotocolsbasedonthedeclarativenetworkandmainlydiscussestheprincipleandrealizationoftheBayesian-estimationbasedadaptivehybridprotocolinthedeclarativenetwork,whichiswelladaptedtotheMobileAdhocNETwork(MANET).Theadaptivehybridprotocolisdesignedforadhocnetworkswhichhavecharacteristicslikeself-organizing,notrustedparty,flexibility,etc.Thenodesthatrunthehybridprotocolcanautomaticallyselectoneroutingprotocolthatissuitablefordifferentnetworkenvironment.TheBayesian-estimationbasedadaptivestrategy,thatimprovestheadaptabilityandstabilityoftheprotocol,succeedsintheRapidnet,adeclarativenetworkengine.TheresultintheRapidnetprovesthatthehybridprotocolandtheadaptivestrategyarefeasible.Theexperimentonthens-3simulator,anemergingdiscrete-eventnetworksimulator,validatesthatthisprotocolperformswellandreducescommunicationoverheads.
简介:活动特定的网络(MANET)是有能是的无线移动式节点的一种很复杂的分布式的通信系统自由地并且动态地self-organizedinto任意、暂时的网络拓扑。MANET继承无线网络的几限制,同时使从MANET的特性产生的新挑战例如线路失败,隐藏终端和暴露的终端。当TCP在MANET环境被使用时,问题不得不被处理的流氓的棕土。在这篇论文,这块动态地上的全面调查被给。明确地,第一次,损害TCP性能的所有因素基于网络协议分级被识别,即,在物理层的有损耗的无线隧道;在MAC层的过多的竞争和不公平的存取;在网络层,MAC层和网络层的脆弱的路由选择协议联系了移动式节点;在传送层和传送层的不适宜的拥挤窗口大小联系了不对称的路径。这些因素怎么降级TCPperformance清楚地被解释。基于怎么减轻每上面列出的这些因素的影响,然后,存在答案尽可能包括地被收集并且分类进很多个范畴,和他们的优点和限制被讨论。这些答案的基于的在限制,为设计更柔韧的答案的一套开的问题被建议。
简介:Inmobileadhocnetworks(MANET),nodesmovefreelyandthedistributionofaccessrequestschangesdynamically.Replicaallocationinsuchadynamicenvironmentisasignificantchallenge.Inthispaoer,adynamicadaptivereplicaallocationalgorithmthatcanadapttothenodesmotionisproposedtominimizethecommunicationcostofobjectaccess.Whenchangesoccurintheaccessrequestsoftheobjectorthenetworktopology,eachreplicanodecollectsaccessrequestsfromitsneighborsandmakesdecisionslocallytoexpandreplicatoneighborsortorelinquishthereplica.Thealgorithmdynamicallyadaptsthereplicaallocationschemetoalocaloptimalone.SimulationresultsshowthatouralgorithmsefficientlyreducethecommunicationcostofobjectaccessinMANETenvironment.
简介:Broadcastisanimportantoperationinmanynetworkprotocols.Itisutilizedtodiscoverroutestounknownnodesinmobileadhocnetworks(MANETs)andisthekeyfactorinscalingon-demandroutingprotocolstolargenetworks.ThispaperpresentstheAdHocBroadcastProtocol(AHBP)anditsperformanceisdiscussed.Intheprotocol,messagesareonlyrebroadcastbybroadcastrelaygatewaysthatconstituteaconnecteddominatingsetofthenetwork.AHBPcanefficientlyreducetheredundantmessageswhichmakeflooding-likeprotocolsperformbadlyinlargedensenetworks.Simulationsareconductedtodeterminetheperformancecharacteristicsoftheprotocol.ThesimulationresultshaveshownexcellentreductionofbroadcastredundancywithAHBP.Italsocontributestoareducedlevelofbroadcastcollisionandcongestion.
简介:Mobileadhocnetworks(MANETs)aregainingalotofattentioninresearchlatelyduetotheirimportanceinenablingmobilewirelessnodestocommunicatewithoutanyexistingwiredorpredeterminedinfrastructures.Furthermore,inordertosupportthegrowingneedformultimediaandrealtimeapplications,qualityofservice(QoS)supportbythenetworkingprotocolisrequired.SeveralimportantQoSparametersthatareneededbysuchapplicationscanbeidentified.Theyincludebandwidth,end-to-enddelay,delayjitter,andbiterrorrate.Agoodamountofresearchhasbeendevelopedinthisareacoveringdifferentissuesandchallengessuchasdevelopingroutingprotocolsthatsupportbandwidthreservationanddelaymanagement.Inthispaper,thecurrentstateofresearchforQoSsupportinTDMA-basedMANETsatdifferentlayersofthenetworkingmodelispresentedandcategorized.Inaddition,thecurrentissuesandfuturechallengesinvolvedinthisexcitingareaofresearcharealsoincluded.
简介:Thispaperfocusesoninvestigatingimmunologicalprinciplesindesigningamulti-agentsecurityarchitectureforintrusiondetectionandresponseinmobileadhocnetworks.Inthisapproach,theimmunity-basedagentsmonitorthesituationinthenetwork.Theseagentscantakeappropriateactionsaccordingtotheunderlyingsecuritypolicies.Specifically,theiractivitiesarecoordinatedinahierarchicalfashionwhilesensing,communicating,decisionandgeneratingresponses.Suchanagentcanlearnandadapttoitsenvironmentdynamicallyandcandetectbothknownandunknownintrusions.Theproposedintrusiondetectionarchitectureisdesignedtobeflexible,extendible,andadaptablethatcanperformreal-timemonitoring.Thispaperprovidestheconceptualviewandageneralframeworkoftheproposedsystem.Intheend,thearchitectureisillustratedbyanexampletoshowitcanpreventtheattackefficiently.
简介:链路缓存可能会使用图的搜索算法找到至目的节点的路由,而使用链路缓存的节点只需删除断开的链路信息,使用了链路缓存和新的链路生存时间估计方法后
简介:Inthispaper,anopportunisticcooperativeadhocsensornetworkwithrandomlylocatednodesisanalyzed.Therandomnessofnodes'locationsiscapturedbyahomogeneousPoissonpointprocess.Theeffectofimperfectinterferencecancellationisalsotakenintoaccountintheanalysis.Basedonthetheoryofstochasticgeometry,outageprobabilityandcooperativegainarederived.Itisdemonstratedthatexplicitperformancegaincanbeachievedthroughcooperation.Theanalysesarecorroboratedbyextensivesimulationresultsandtheanalyticalresultscanthusserveasaguidelineforwirelesssensornetworkdesign.