通信基本原理,主流的通信技术,短波微波卫星ATMTCPIPAAA路由和MPLS

Application-driven,energy-efficientcommunicationinwirelesssensornetworks

Severalsensornetworkapplicationsbasedondatadiffusionanddatamanagementcandeterminethecommunicationtransferratebetweentwosensorsbeforehand.Inthisframework,weconsidertheproblemofenergyefficientcommunicationamongnodesofawirelesssensornetworkandproposeanapplication-drivenapproachthatminimizesradioactivityintervalsandprolongsnetworklifetime.Onthebasisofpossiblecommunicationdelaysweestimatepacketarrivalintervalsatanyintermediatehopofafixed-ratedatapath.Westudyagenericstrategyofradioactivityminimizationwhereineachnodemaintainstheradioswitchedonjustintheexpectedpacketarrivalintervalsandguaranteeslowcommunicationlatency.Wedefineaprobabilisticmodelthatallowstheevaluationofthepacketlossprobabilitythatresultsfromthereducedradioactivity.Themodelcanbeusedtooptimallychoosetheradioactivityintervalsthatachieveacertainprobabilityofsuccessfulpacketdeliveryforaspecificradioactivitystrategy.Relyingontheprobabilisticmodelwealsodefineacostmodelthatestimatestheenergyconsumptionoftheproposedstrategies,underspecificsettings.Weproposethreespecificstrategiesandnumericallyevaluatetheassociatedcosts.WefinallyvalidateourworkwithasimulationmadewithTOSSIM(theBerkeleymotes’simulator).Thesimulationresultsconfirmthevalidityoftheapproachandtheaccuracyoftheanalyticmodels.ArticleOutline1.Introduction2.Relatedwork3.Scenario4.Communicationparadigm5.Probabilisticmodel5.1.Successandfailureprobabilities5.2.Costestimation6.Optimizationofthecostfunction7.Alternativestrategiesforw(i)7.1.Analysisofthestrategiesfix,lin,andmix8.Simulations9.ConclusionsHYPERLINKThechangingusageofamaturecampus-widewirelessnetwork

无线局域网络在数字化校园/社区/办公区旳创新应用校园无线通信网络及其产品市场开发WirelessLocalAreaNetworks(WLANs)arenowcommonplaceonmanyacademicandcorporatecampuses.As“Wi-Fi”technologybecomesubiquitous,itisincreasinglyimportanttounderstandtrendsintheusageofthesenetworks.Thispaperanalyzesanextensivenetworktracefromamature802.11WLAN,includingmorethan550accesspointsand7000usersoverseventeenweeks.Weemployseveralmeasurementtechniques,includingsyslogmessages,telephonerecords,SNMPpollingandtcpdumppacketcaptures.ThisisthelargestWLANstudytodate,andthefirsttolookatamatureWLAN.Wecomparethistracetoatracetakenafterthenetwork’sinitialdeploymenttwoyearsprior.WefoundthattheapplicationsusedontheWLANchangeddramatically,withsignificantincreasesinpeer-to-peerandstreamingmultimediatraffic.DespitetheintroductionofaVoiceoverIP(VoIP)systemthatincludeswirelesshandsets,ourstudyindicatesthatVoIPhasbeenusedlittleonthewirelessnetworkthusfar,andmostVoIPcallsaremadeonthewirednetwork.Wesawgreaterheterogeneityinthetypesofclientsused,withmoreembeddedwirelessdevicessuchasPDAsandmobileVoIPclients.Wedefineanewmetricformobility,the“sessiondiameter”.Weusethismetrictoshowthatembeddeddeviceshavedifferentmobilitycharacteristicsthanlaptops,andtravelfurtherandroamtomoreaccesspoints.Overall,usersweresurprisinglynon-mobile,withhalfremainingclosetohomeabout98%ofthetime.ArticleOutline1.Introduction2.Thetestenvironment2.1.VoiceoverIP2.2.Clientdevices3.Tracecollection3.1.Syslog3.2.SNMP3.3.Ethernetsniffers3.4.VoIPCDRdata3.5.Definitions3.6.Definingmobility4.Changes4.1.Clients4.2.Traffic5.Specificapplications5.1.VoIP5.2.Peer-to-peerapplications5.3.Streamingmedia6.Mobility7.Relatedwork8.Conclusionsandrecommendations8.1.FutureworkAcknowledgementsReferencesHYPERLINKCollaborativedatagatheringinwirelesssensornetworksusingmeasurementco-occurrence

并发性事件旳衡量/确认和信息协同化收集无线传感器网络技术与建设Wirelessadhocnetworksofbattery-poweredmicrosensors(WSNs)areproliferatingrapidlyandtransforminghowinformationisgatheredandprocessed,andhowweaffectourenvironment.Thelimitedenergyofthosesensorsposesthechallengeofusingsuchsystemsinanenergyefficientmannertoperformvariousactivities.AcommonactivityofmanyapplicationsofWSNsisthatofdatagathering:foreachtimestep,gatherthemeasurementfromeachsensortoabasestation.Oftenthereisredundancyand/ordependencyamongthesensormeasurements.Howtoidentifythedataredundancy/dependencyandutilizethemonimprovingenergyefficiencyofdatagatheringhasbeenoneoftheattractivetopics.Weproposeusingmeasurementco-occurrencetoidentifydataredundancyandanovelcollaborativedatagatheringapproachutilizingco-occurrencethatoffersatrade-offbetweenthecommunicationcostofdatagatheringversuserrorsatestimatingthesensormeasurementsatthebasestation.Akeytenantofourapproachistohavesensorswithco-occurringmeasurementsalternateintransmittingsuchco-occurringmeasurementstothebasestation,andhavingthebasestationmakeinferencesaboutthesensormeasurementsutilizingonlythedatatransmittedtoit.Wepresenttwoeffectivein-networkmethodsfordetectingco-occurrenceofmeasurements,aswellasasimpleandefficientprotocolforschedulingthetransmissionofthesensormeasurementstothebasestation.Weprovideexperimentalresultsonsyntheticandrealdatasetsshowingthattheproposedsystemofferssubstantial(upto65%)reductionofthecommunicationcostsofdatagatheringwithasmallnumberofmeasurementinferenceerrors(<6%)atthebasestation.ArticleOutline1.Introduction2.Estimatingco-occurrenceofsensormeasurements2.1.Measurementco-occurrence2.2.Estimatingtheresemblanceofoccurrencesets2.2.1.Positionalmin-wisehashing2.2.2.Randomprojection2.2.3.Mis-identificationerrors2.2.4.Elementsignatures3.Collaborativedatagatheringprotocolexploitingmeasurementsco-occurrence3.1.Analysisofthecostsoftheprotocol4.Experimentalevaluation4.1.Datasetsandperformancemetrics4.2.Experimentalresults–syntheticdatasets4.3.Experimentalresults–realdataset5.Relatedwork5.1.Setresemblanceestimation5.2.Collaborativedatagathering6.ConclusionAppendixAAppendixBAppendixC.

HYPERLINKDynamicend-to-endcapacityinIEEE802.16wirelessmeshnetworks

IEEE合同下无线网络旳动态端到端访问能力/容量TheIEEE802.16standarddefinesmeshmodeasoneofitstwooperationalmodesinmediumaccesscontrol(MAC).Inthemeshmode,peer-to-peercommunicationbetweensubscriberstations(SSs)isallowed,andtransmissionscanberoutedviaotherSSsacrossmultiplehops.InsuchanIEEE802.16meshnetwork,accurateandreliabledeterminationofdynamiclinkcapacityandend-to-endcapacityofagivenmulti-hoprouteiscrucialforrobustnetworkcontrolandmanagement.Thedynamiccapacitiesaredifficulttodetermineinadistributedsystemduetodecentralizedpacketschedulingandinterferencebetweencommunicatingnodescausedbythebroadcastnatureofradiopropagation.Inthispaper,wefirstproposeamethodforcomputingthedynamiclinkcapacitybetweentwomeshnodes,andextendthattodeterminethedynamicend-to-endcapacityboundsofamulti-hoproutebasedontheconceptofBottleneckZone.Thephysicaldeploymentsofnetworksarealsoconsideredinthecapacityestimation.Wedemonstratetheeffectivenessandaccuracyofourmethodsforcomputingdynamiclinkcapacityandend-to-endcapacityboundsthroughextensivesimulations.ArticleOutline1.Introduction2.OverviewofIEEE802.16meshmode3.LinkcapacityinIEEE802.16meshnetworks3.1.Transmissionschedulinginwirelessmeshnetworks3.2.Linkcapacitycomputation4.End-to-endcapacityinIEEE802.16wirelessmeshnetworks4.1.Concurrenttransmissionsingenericwirelessnetworks4.2.Definitions4.3.End-to-endcapacityboundsindensenetworksoroptimallydeployednetworkswithIEEE802.16meshconfiguration4.4.End-to-endcapacityboundsinrandomnetworkswithIEEE802.16meshconfiguration5.Simulationresults5.1.Optimaldeployment5.1.1.StringTopologies5.1.2.Regularmeshtopology5.2.Randomdeployment6.Relatedwork7.ConclusionsandfutureworkAcknowledgementsAppendixA.ProofofTheorem1AppendixB.ProofofTheorem2AppendixC.ProofofTheorem4ReferencesHYPERLINKVehiculartelematicsoverheterogeneouswirelessnetworks:Asurvey

Thisarticlepresentsasurveyonvehiculartelematicsoverheterogeneouswirelessnetworks.Anadvancedheterogeneousvehicularnetwork(AHVN)architectureisoutlinedwhichusesmultipleaccesstechnologiesandmultipleradiosinacollaborativemanner.ThechallengesindesigningtheessentialfunctionalcomponentsofAHVNandthecorrespondingprotocols(forradiolinkcontrol,routing,congestioncontrol,securityandprivacy,andapplicationdevelopment)arediscussedandtherelatedworkintheliteraturearereviewed.Theopenresearchchallengesandseveralavenuesforfutureresearchonvehiculartelematicsoverheterogeneouswirelessaccessnetworksareoutlined.ArticleOutline1.Introduction2.Vehiculartelematicapplicationsandrequirements3.AdvancedHeterogeneousVehicularNetwork(AHVN)architectureforvehiculartelematics3.1.Theaccesstechnologyoptions3.2.Theessentialfunctionalcomponentsandtheirlogicalrelations4.DesigningtheAHVNarchitecture:challengesandapproaches4.1.Selectionofaccessnetwork4.2.NetworkselectionVs.linkselectionVer-systemhandoff4.3.Hierarchicaldesign4.4.Operatingsystemandapplicationmanagement5.DesigningtheAHVNprotocols:challengesandapproaches5.1.Wirelessaccessstrategies5.2.MACprotocols5.2.1.MACProtocolsforV2RNetworks5.2.2.MACprotocolsforV2Vnetworks5.3.Datadisseminationprotocols5.4.Dataaggregationprotocols5.5.Routingprotocols5.6.Congestioncontrolprotocols5.6.1.Window-basedcongestioncontrolalgorithms5.6.2.Rate-basedcongestioncontrolalgorithms5.7.Cross-layerprotocoldesigninvehicularnetworks5.8.Securityprotocols5.8.1.PKI-basedarchitectures5.8.2.Hybridsecurityarchitecturesforvehicularnetworks5.8.3.Enhancingsecuritybydataaggregation,validation,andcorrection5.9.Privacyprotocols6.OpenissuesandresearchdirectionsAcknowledgementsHYPERLINKOptimizednetworkmanagementforenergysavingsofwirelessaccessnetworks

Theenergyconsumptionofwirelessaccessnetworksisrapidlyincreasingandinsomecountriesitamountsformorethan55%ofthewholecommunicationsectorandforanonnegligiblepartoftheoperationalcostsofmobileoperators.Thenewwirelesstechnologieswithagrowthofdataratesbyafactorofroughly10every5

yearsandtheincreaseinthenumberofusersresultinadoublingofthepowerconsumptionofcellularnetworksinfrastructureevery4–5years–to60

TWhin.Inthispaperweconsiderpossibleenergysavingsthroughoptimizedmanagementofon/offstateandtransmittedpowerofaccessstationsaccordingtotrafficestimatesindifferenthoursofthedayordaysoftheweek.WeproposeanoptimizationapproachbasedonsomeILPmodelsthatminimizesenergyconsumptionwhileensuringareacoverageandenoughcapacityforguaranteeingqualityofservice.Proposedmodelscapturesystemcharacteristicsconsideringdifferentmanagementconstraintsthatcanbeconsideredbasedontrafficrequirementsandapplicationscenarios.Energyminimizationproblemsaresolvedtotheoptimumorwithagaptotheoptimumoflessthan2.7%onasetofsyntheticinstancesthatarerandomlygenerated.Obtainedresultsshowthatremarkableenergysavings,uptomorethan50%,canbeobtainedwiththeproposedmanagementstrategies.ArticleOutline1.Introduction2.Relatedwork3.Powerconsumptionmodel3.1.APpowerconsumption3.2.Transmittedpowerandcoveragerange4.Networkandtrafficmodel4.1.Structureoftheservicearea4.2.Capacityloadestimation4.3.Trafficpatternfordifferenttimeperiods4.4.Modelingtrafficdistribution5.Energyconsumptionminimization5.1.Formulationofoptimizationmodels5.2.Basicenergyoptimizationmodel5.3.Modelingcompletecoverage5.4.Limitingconfigurationvariations5.5.Guaranteedpoweringofnetworkdevices6.Instancegeneratorandreferencemodels6.1.Generatorofinputdata6.2.Modelsforenergycomparison7.Numericalresults7.1.Resultsonsmallinstances7.2.Resultsonrealisticinstance7.3.Energysavings7.4.Furtherextensionsofthemodels8.ConclusionAcknowledgementsReferences无线网络安装部署旳优化管理与规划设计基于节能和可访问性旳角度HYPERLINKWirelesscommunicationsdeploymentinindustry:areviewofissues,optionsandtechnologies

ComputersinIndustryPresentbasisofknowledgemanagementistheefficientshareofinformation.Thechallengesthatmodernindustrialprocesseshavetofacearemultimediainformationgatheringandsystemintegration,throughlargeinvestmentsandadoptingnewtechnologies.Drivenbyanotablecommercialinterest,wirelessnetworkslikeGSMorIEEE802.11arenowthefocusofindustrialattention,becausetheyprovidenumerousbenefits,suchaslowcost,fastdeploymentandtheabilitytodevelopnewapplications.However,wirelessnetsmustsatisfyindustrialrequisites:scalability,flexibility,highavailability,immunitytointerference,securityandmanyothersthatarecrucialinhazardousandnoisyenvironments.Thispaperpresentsathoroughsurveyofallthisrequirements,reviewstheexistingwirelesssolutions,andexplorespossiblematchingbetweenindustryandthecurrentexistingwirelessstandards.1.Introduction2.Relatedwork3.Communicationsystemsinindustry3.1.Fieldlevel3.2.Industrialenvironmentrequirements3.3.Wirelessinindustry4.Wirelesstechnologysurvey4.1.Generaloverview4.2.Commonbenefitsofwirelessnetworks4.3.Problemsanddisadvantages4.4.Regulationissues4.4.1.Spectrumregulationissues4.4.2.Industrialandsecurityregulationissues4.4.3.Radiofrequencysafetyregulationissues4.5.Securityissues4.6.Radioemissionsissues4.6.1.Noiseandmediaeffectsoncommunications4.6.2.Environmentalimpact4.6.3.Healthissues4.7.NetworksTaxonomyandTechnologicaldescription4.7.1.Historicalpreview4.7.2.Cellulartelephonysystems.GSM.GPRSandEDGE.UMTS.Industrialapplicationsofcellularnetworks4.7.3.Localloopsubstitutes.LMDSandMMDS.IndustrialapplicationsofWLL4.7.4.Trunking.TETRA.IndustrialapplicationsofTETRA4.7.5.Indoorwirelesscommunications.DECT.IndustrialapplicationofDECT4.7.6.Wirelesslocalareanetworks.IEEE802.11andHIPERLAN4.7.7.WirelessPersonalAreaNetworks.Bluetooth,IEEE802.15andIrDA4.8.Complementarytechnologies4.8.1.RFTagssystems4.8.2.Positioningsystems5.Applicationsofwirelesssystemsinindustry5.1.Applicationscenarios5.1.1.Examplesofmanagementprocesses5.1.2.Examplesofproductionprocesses.Newapplicationscenario:ashipyard6.ConclusionsAcknowledgementsReferences无线通信网在工业、生产、物流、过控中旳应用调查：有关技术动态设备选型注意事项等HYPERLINKCapacityboundsofdeploymentconceptsforWirelessMeshNetworks

PerformanceEvaluationLocalareawirelessnetworksarelikecellularsystems:Stationsassociatetooneoutofseveralaccesspoints(APs),whichconnecttoawiredbackbone.Duetosignalattenuationandtransmissionpowerlimitations,radioconnectivityisavailableonlysufficientlyclosetoanAP.InscenarioswithadensedeploymentofAPsthewiredbackbonecausesunprofitablyhighcosts.AWirelessMeshNetwork(WMN)servestoextendthecoverageofAPsbymeansofMeshPoints(MPs)thatforwarddatabetweenastationandanAP.Thisconceptreducesdeploymentcosts,butreducesalsonetworkcapacity,owingtomultipletransmissionsofthesamedatapacketonitsmulti-hoproute.Thispaperanalyzeshowthecapacityofcost-limitedWMNscanbeoptimized.AlayeredmodelofaWMNspecifyingthetypicalcharacteristicsofthenetworkisusedtocalculatetheuppercapa