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Unit2TextAMobileWirelessOverviewMobileWirelessOverviewAfast-pacedtechnologicaltransitionisoccurringtodayintheworldofinternetworking.ThistransitionismarkedbytheconvergenceofthetelecommunicationsinfrastructurewiththatofIPdatanetworkingtoprovideintegratedvoice,video,anddataservices.TextTextWordsNotesDiscussionHomeAsthistransitionprogresses,thecorrespondingstandardsarecontinuingtoevolveandmanynewstandardsarebeingdevelopedtoenableandacceleratethisconvergenceoftelecommunicationsandIPnetworkingtomobilizetheinternetandprovidenewmultimediaservices.TextTextWordsNotesDiscussionHome1.IntroductiontoMobileWirelessTechnologyThetechnologiesrelatedtowirelesscommunicationcanbecomplextodifferentiate.Wirelesstechnologyhasbeenaroundforawhile;however,therehasbeenarelativelyrecentandrapidsurgeintheevolutionofnewwirelessstandardstosupporttheconvergenceofvoice,videoanddatacommunication.Muchofthisrapidevolution,orrevolution,isaresultofpeopleseekingubiquitousandimmediateaccesstoinformationandtheassimilationoftheinternetintobusinesspracticesandforpersonaluse.People“onthego”wanttheirinternetaccesstomovewiththem,sothattheirinformationisavailableatanytime,anywhere.TextWordsNotesDiscussionHomeTherearemanyfactorsthatcanbeusedtocharacterizewirelesstechnologies:•Spectrum,ortherangeoffrequenciesinwhichthenetworkoperates•Transmissionspeedssupported•Underlyingtransmissionmechanism,suchasfrequencydivisionmultipleaccess(FDMA),timedivisionmultipleaccess(TDMA),orcodedivisionmultipleaccess(CDMA)•Architecturalimplementation,suchasenterprisebased(orin-building),fixed,ormobileTextWordsNotesDiscussionHomeInaddition,themobilewirelesstechnologies[suchasGlobalSystemforMobileCommunications(GSM),TDMA,CDMA]aredifferentiatedbyanumberofdifferentfactors,includingsomeofthefollowing:•Controlofthetransmittedpower•Radioresourcemanagementandchannelallocation•Codingalgorithms•Networktopologyandfrequencyreuse•HandoffmechanismsTextWordsNotesDiscussionHomeAssuggestedbyitsname,mobilewirelesscommunicationaddressesthosewirelesstechnologiesthatsupportmobilityofasubscriber,whichprovideseamlessandreal-timeserviceswithoutinterruption.[1]Mobilewirelesstechnologiessupportnetworkaccesswhethersubscribersroamwithinoroutsidetheirhomewirelesscoveragearea.TextWordsNotesDiscussionHome2.OverviewofBasicNetworkElementsAssociatedwithCellularNetworksandMobileWirelessThissectionprovidesabriefintroductiontoafewofthebasicnetworkcomponentsassociatedwiththeexistingtelecommunicationsinfrastructure.ItspecificallydiscussestheexistingmobilewirelessnetworkinfrastructurecomponentsforTDM-basedwirelessnetworks,someofwhicheventuallywillbereplacedbynewIP-basedcomponents.TextWordsNotesDiscussionHomeIntheearly1980s,supportformobilewirelesscommunicationswasintroducedusingcellularnetworks,whichwerebasedonanalogtechnologiessuchasAMPS[2].Manyofthetelecommunicationsentitiesassociatedwithcellularnetworksstillplayavitalroleintoday’swirelessnetworks.AswirelesscommunicationstechnologiescontinuetoprogressandIPdatanetworkingisfurtherintegratedintotheexistinginfrastructure,someofthefunctionsoftheseentitiesmightstillexistwithinthenetwork,butwillbeimplementedindifferentandmoreeffectiveways.TextWordsNotesDiscussionHomeThefollowingnetworkelementsarepartofatypicalcellulartelecommunicationsnetwork:•PublicSwitchedTelephoneNetwork(PSTN)•MobileSwitchingCenter(MSC)•BaseStation(BS)•RadioAccessNetwork(RAN)•HomeLocationRegister(HLR)•VisitorLocationRegister(VLR)•AuthenticationCenter(AC)

[3]TextWordsNotesDiscussionHome(1)PublicSwitchedTelephoneNetwork(PSTN)ThePSTNisthefoundationandremainsthepredominantinfrastructurethatcurrentlysupportstheconnectionofmillionsofsubscribersworldwide.ThePSTNhasseveralthousandsofmilesoftransmissioninfrastructure,includingfixedlandlines,microwave,andsatellitelinks.Aftertheintroductionofcellulartelephonesystemsintheearlyandmid-1980s,andwiththerapiddevelopmentofmobilewirelesscommunicationservices,thePSTNstillprovidesthefixednetworksupportusingtheSignalingSystemNumber7(SS7)protocoltocarrycontrolandsignalingmessagesinapacket-switchedenvironment.TextWordsNotesDiscussionHome(2)MobileSwitchingCenter(MSC)TheMSC,usuallylocatedattheMobileTelephoneSwitchingOffice(MTSO),ispartofthemobilewirelessnetworkinfrastructurethatprovidesthefollowingservices:•SwitchesvoicetrafficfromthewirelessnetworktothePSTNifthecallisamobile-to-landlinecall,oritswitchestoanotherMSCwithinthewirelessnetworkifthecallisamobile-to-mobilecall.•Providestelephonyswitchingservicesandcontrolscallsbetweentelephoneanddatasystems.TextWordsNotesDiscussionHome•Providesthemobilityfunctionsforthenetworkandservesasthehubforuptoasmanyas100BSs.Morespecifically,theMSCprovidesthefollowingfunctions:•Mobilitymanagementforthesubscribers(toregistersubscribers,toauthenticateandauthorizethesubscribersforservicesandaccesstothenetwork,tomaintaintheinformationonthetemporarylocationofthesubscriberssotheycanreceiveandoriginatevoicecalls).TextWordsNotesDiscussionHomeInGSM,someofthefunctionalityoftheMSCisdistributedtotheBaseStationController(BSC).InTDMA,theBSCandtheMSCareintegrated.•Callsetupservices(callroutingbasedonthecallednumber).ThesecallscanbetoanothermobilesubscriberthroughanotherMSC,ortoalandlineuserthroughthePSTN.•Connectioncontrolservices,whichdeterminehowcallsareroutedandestablishestrunkstocarrythebearertraffictoanotherMSCortothePSTN.TextWordsNotesDiscussionHome•Servicelogicfunctions,whichroutethecalltotherequestedserviceforthesubscriber,suchasan800service,callforwarding,orvoicemail.•Transcodingfunctions,whichdecompressthevoicetrafficfromthemobiledevicegoingtothePSTNandcompressesthetrafficgoingfromthePSTNtothemobiledevice.TextWordsNotesDiscussionHome(3)BaseStation(BS)TheBSisthecomponentofthemobilewirelessnetworkaccessinfrastructurethatterminatestheairinterfaceoverwhichthesubscribertrafficistransmittedtoandfromamobilestation(MS).InGSM-basednetworks,theBSiscalledaBaseTransceiverStation(BTS).TextWordsNotesDiscussionHome(4)RadioAccessNetwork(RAN)TheRANidentifiestheportionofthewirelessnetworkthathandlestheradiofrequencies(RF),RadioResourceManagement(RRM),whichinvolvessignaling,andthedatasynchronizationaspectsoftransmissionovertheairinterface.TextWordsNotesDiscussionHomeInGSM-basednetworks,theRANtypicallyconsistsofBTSsandBaseStationControllers(BSCs).UsersessionsareconnectedfromamobilestationtoaBTS,whichconnectstoaBSC.ThecombinedfunctionsoftheBTSandBSCarereferredtoastheBaseStationSubsystem(BSS)[4].TextWordsNotesDiscussionHome(5)HomeLocationRegister(HLR)TheHLRisadatabasethatcontainsinformationaboutsubscriberstoamobilenetworkthatismaintainedbyaparticularserviceprovider.Inaddition,forsubscribersofaroamingpartner,theHLRmightcontaintheserviceprofilesofvisitingsubscribers.TextWordsNotesDiscussionHomeTheMSCusesthesubscriberinformationsuppliedbytheHLRtoauthenticateandregisterthesubscriber.TheHLRstores“permanent”subscriberinformation(ratherthantemporarysubscriberdata,whichaVLRmanages),includingtheserviceprofile,locationinformation,andactivitystatusofthemobileuser.TextWordsNotesDiscussionHome(6)VisitorLocationRegister(VLR)TheVLRisadatabasethatismaintainedbyanMSC,tostoretemporaryinformationaboutsubscriberswhoroamintothecoverageareaofthatMSC.TheVLR,whichisusuallypartofanMSC,communicateswiththeHLRoftheroamingsubscribertorequestdata,andtomaintaininformationaboutthesubscriber’scurrentlocationinthenetwork.TextWordsNotesDiscussionHome(7)AuthenticationCenter(AC)TheACprovideshandsetauthenticationandencryptionservicesforaserviceprovider.Inmostwirelessnetworkstoday,theACiscollocatedwiththeHLR,andisoftenimplementedaspartoftheHLRcomplex.TextWordsNotesDiscussionHome3.ModelforIPIntegrationintoMobileWirelessThestandardsfortheintegrationofIPdatanetworkingwiththeexistingtelecommunicationsinfrastructurearerapidlydevelopingandbeginningtoberealizedintoday’sproductionnetworks.TextWordsNotesDiscussionHomeFigure1 IPIntegrationPhasesinMobileWirelessTextWordsNotesDiscussionHomeFigure1showsamodelforIPintegrationbaseduponthecurrentindustrydirectionandreflectssomeofthelatestideaswithintheMobileWirelessInternetForum(MWIF).TheMWIFisapre-standardsconsortiumforserviceprovidersandsupplierstocollaborateontheimplementationofIP-basedmobilewirelessnetworks.TheMWIFinfluencesthestandardsbodiessuchas3GPPand3GPP2tosuccessfullyadoptnewimplementations.Inparticular,Figure1showswhereCiscoSystems’GGSNproductforGSMnetworksfitsintothemodel.TextWordsNotesDiscussionHomeThetoptwoquadrantsinFigure1showwherewearetodayinthetelecommunicationsandIPdataservicesinfrastructures.Thefirstquadrantrepresentsthefirstphaseoftheseinfrastructuresbasedoncircuit-switchedvoiceanddataservices.ThebeginningsofacoreIPtransportforvoiceanddataintegrationcanbebuiltusingCiscoSystemsV.110solutions.TextWordsNotesDiscussionHomeThesecondquadrantdepictstheimplementationphaseof2G+technologies,suchasGPRS,supportinghighertransmissionspeeds.Inthisquadrant,theCiscoSystemsGGSNprovidesIPpacketdataservices.ItactsasanIPgatewayforaccesstotheinternetandotherpublicandprivatedatanetworksfortrafficthatisinitiatedinaGSM-basedmobileenvironment.Theservicesanticipatedinthisphaseincludeimplementingalways-ondataservicesandenablingoperatorstochargebypacketratherthanconnecttime.SimilarservicesaresupportedbyPacketDataServicesNode(PDSN),forCDMA-basedwirelessnetworks.TextWordsNotesDiscussionHomeThethirdquadrantrepresentsphasethreeoftheintegrationofIPnetworkingwherevoiceanddataareconsolidatedontoapacket-basedinfrastructurefromtheRANorradionetworkcontrol(RNC)outward.Thisisconsidereda3Gsolution.Phasethreeenablesintegratedvoiceanddataapplicationsandreducescosts.Inaddition,someofthecomponentsorfunctionsoftheMSCaredistributed.TextWordsNotesDiscussionHomeThefourthquadrantrepresentsthefinalphase,whichincludes3GservicesplustheimplementationofIP-basedradioandmobilitycomponentstodevelopatrueend-to-end,all-IPwirelessnetworksolution.TextWordsNotesDiscussionHomeconvergencen.趋同;集收敛;集合,会聚;[气]辐合infrastructuren.基础结构,基础架构;基础设施;基础建设differentiatev.区分,辨别;使不同ubiquitousadj.无所不在的,普遍存在的assimilationn.吸收,消化subscribern.用户,订户WordsWordsTextWordsNotesDiscussionHomeseamlessadj.无缝的;无漏洞的roamv.&n.漫游,漫步cellularadj.蜂窝状的;细胞的analogadj.[电]模拟的;(钟表)有长短针的implementvt.实施,执行;使生效hubn.(电器面板上的)电线插孔;[计]集线器WordsTextWordsNotesDiscussionHomeauthenticatevt.使生效;鉴别encryptionn.编密码;加密decompressvt.解压compressvt.压紧;压缩;精简synchronizationn.同步,使时间互相一致profilen.人物简介;外形,轮廓WordsTextWordsNotesDiscussionHomeconsortiumn.组合,共同体;财团quadrantn.象限仪,四分仪gatewayn.网关;入口;途径WordsTextWordsNotesDiscussionHome[1]Assuggestedbyitsname,mobilewirelesscommunicationaddressesthosewirelesstechnologiesthatsupportmobilityofasubscriber,whichprovideseamlessandreal-timeserviceswithoutinterruption.顾名思义,移动无线通信用以称呼那些支持用户流动性的无线技术,它能够提供无缝连接和不间断的实时业务。TextWordsNotesDiscussionNotesHome[2]AMPS是第一代蜂窝技术,使用单独的频带,或者说“信道”,为每次对话服务。它因此需要相当的带宽来支持一个大数量的用户群体。在通用术语中,AMPS常常被当作更早的“0G”改进型移动通信服务,只不过AMPS使用更多的计算功率来选择频谱、切换到PSTN线路的通话、以及处理登记和呼叫建立。真正将AMPS从更早的0G系统中区分出来的是最后的呼叫建立功能。在AMPS中,蜂窝中心可以根据信号强度灵活地分配信道给每个手持终端,允许相同的频率在完全不同的位置复用,并且不会有干扰。这使得在一个地区内,大数量的手持终端被同时支持成为可能。AMPS的创始者们发明了“蜂窝”这个术语正是因为它在一个系统里使用的都是小的六边形“蜂窝”形状。TextWordsNotesDiscussionHome[3]AuthenticationCenter(AUC):称为鉴权中心,是GSM系统中的安全管理单元,存储鉴权算法和密钥,保证各种保密参数的安全性,向HLR(归属用户位置寄存器)提供鉴权参数。鉴权参数包括三组:RAND(RandomNumber,随机数),SRES(SignResponse,符号响应),Kc(CipheringKey,加密密钥)。

TextWordsNotesDiscussionHome[4]BaseStationSubsystem(BSS):指基站子系统,是移动通信系统中与无线蜂窝网络关系最直接的基本组成部分。在整个移动网络中基站主要起中继作用。基站与基站之间采用无线信道连接,负责无线发送、接收和无线资源管理。而主基站与移动交换中心(MSC)之间常采用有线信道连接,实现移动用户之间或移动用户与固定用户之间的通信连接。TextWordsNotesDiscussionHomeQuestionsfordiscussion1.Whatarethebasicelementsofwirelesstechnologies?2.Whatcomponentsisatypicalcellulartelecommunicationsnetworkmadeupof?3.WhatisMSC?Whatdoesitserveasinthemobilewirelessnetworkinfrastructure?4.WhatisHLRandVLR?Whataretheirfunctions?TextWordsNotesDiscussionHomeAnswerstoquestionsfordiscussionTextWordsNotesDiscussionHome1.Whatarethebasicelementsofwirelesstechnologies?Spectrum,ortherangeoffrequenciesinwhichthenetworkoperatesTransmissionspeedssupportedUnderlyingtransmissionmechanism,suchasfrequencydivisionmultipleaccess(FDMA),timedivisionmultipleaccess(TDMA),orcodedivisionmultipleaccess(CDMA)Architecturalimplementation,suchasenterprisebased(orin-building),fixed,ormobileTextWordsNotesDiscussionHome2.Whatcomponentsisatypicalcellulartelecommunicationsnetworkmadeupof?Atypicalcellulartelecommunicationsnetworkconsistsofthefollowingcomponents:PublicSwitchedTelephoneNetwork(PSTN)MobileSwitchingCenter(MSC)BaseStation(BS)RadioAccessNetwork(RAN)HomeLocationRegister(HLR)VisitorLocationRegister(VLR)AuthenticationCenter(AC)TextWordsNotesDiscussionHome3.WhatisMSC?Whatdoesitservesasinthemobilewirelessnetworkinfrastructure?MSC,namely,mobileswitchingcenterusually,islocatedattheMobileTelephoneSwitchingOffice,whichispartofthemobilewirelessnetworkinfrastructure.ThemajorfunctionsofMSCinclude:SwitchingvoicetrafficfromthewirelessnetworktothePSTN;itswitchestoanotherMSC.Providingtelephonyswitchingservicesandcontrolscallsbetweentelephoneanddatasystems.Providingthemobilityfunctionsforthenetworkandservesasthehubforuptoasmanyas100BSs.TextWordsNotesDiscussionHome4.WhatisHLRandVLR?Whataretheirfunctions?HomeLocationRegister(HLR)isadatabasethatcontainsinformationaboutsubscriberstoamobilenetworkthatismaintainedbyaparticularserviceprovider.AndVisitorLocationsRegister(VLR)isadatabasethatismaintainedbyanMSC,tostoretemporaryinformationaboutsubscriberswhoroamintothecoverageareaofthatMSC.TheHLRstores“permanent”subscriberinformation(ratherthantemporarysubscriberdata,whichaVLRmanages),includingtheserviceprofile,locationinformation,andactivitystatusofthemobileuser.TheVLR,whichisusuallypartofanMSC,communicateswiththeHLRoftheroamingsubscribertorequestdata,andtomaintaininformationaboutthesubscriber’scurrentlocationinthenetworkTextWordsNotesDiscussionHomeThankyou!Unit2TextB2G,3G,4G,4GLTE,5G—WhatareThey?2G,3G,4G,4GLTE,5G

—WhatareThey?Quitesimply,the“G”standsforGeneration,asinthenextgenerationofwirelesstechnologies.Eachgenerationissupposedlyfaster,moresecureandmorereliable.Thereliabilityfactoristhehardestobstacletoovercome.1Gwasnotusedtoidentifywirelesstechnologyuntil2G,orthesecondgeneration,wasreleased.Thatwasamajorjumpinthetechnologywhenthewirelessnetworkswentfromanalogtodigital.It’salluphillfromthere.3Gcamealongandofferedfasterdatatransferspeeds,atleast200kilobitspersecond,formulti-mediauseandwasalongtimestandardforwirelesstransmissionsregardlessofwhatyouheardonallthosecommercials.TextTextWordsNotesDiscussionHomeItisstillachallengetogetatrue4Gconnection,whichpromisesupwardsofa1Gps,Gigabitpersecond,transferrateifyouarestandingstillandintheperfectspot.4GLTE[1]comesveryclosetoclosingthisgap.True4Gonawidespreadbasismaynotbeavailableuntilthenextgenerationarrives.5G?TextTextWordsNotesDiscussionHome1.WhataretheStandardsoftheG's?EachoftheGenerationshasstandardsthatmustbemettoofficiallyusetheGterminology.Thosestandardsaresetby,youknow,thosepeoplethatsetstandards.Thestandardsthemselvesarequiteconfusingbuttheadvertiserssureknowhowtomanipulatethem.Iwilltrytosimplifythetermsabit.TextTextWordsNotesDiscussionHome-1GAtermneverwidelyuseduntil2Gwasavailable.Thiswasthefirstgenerationofcellphonetechnology.Simplephonecallswereallitwasabletodo.-2GThesecondgenerationofcellphonetransmission.Afewmorefeatureswereaddedtothemenusuchassimpletextmessaging.-3GThisgenerationsetthestandardsformostofthewirelesstechnologywehavecometoknowandlove.Webbrowsing,email,videodownloading,picturesharingandotherSmartphonetechnologywereintroducedinthethirdgeneration.3Gshouldbecapableofhandlingaround2Megabitspersecond.TextTextWordsNotesDiscussionHome-4GThespeedandstandardsofthistechnologyofwirelessneedstobeatleast100Megabitspersecondandupto1Gigabitpersecondtopassas4G.Italsoneedstosharethenetworkresourcestosupportmoresimultaneousconnectionsonthecell.Asitdevelops,4GcouldsurpassthespeedoftheaveragewirelessbroadbandhomeInternetconnection.Fewdeviceswerecapableofthefullthrottlewhenthetechnologywasfirstreleased.Coverageoftrue4Gwaslimitedtolargemetropolitanareas.Outsideofthecoveredareas,4Gphonesregressedtothe3Gstandards.(tobecontinued)TextTextWordsNotesDiscussionHome(continued)When4Gfirstbecameavailable,itwassimplyalittlefasterthan3G.4Gisnotthesameas4GLTEwhichisveryclosetomeetingthecriteriaofthestandards.Themajorwirelessnetworkswerenotactuallylyingtoanyonewhen4Gfirstrolledout,theysimplystretchedthetruthabit.A4Gphonehadtocomplywiththestandardsbutfindingthenetworkresourcestofulfillthetruestandardwasdifficult.Youwerebuying4Gcapabledevicesbeforethenetworkswerecapableofdeliveringtrue4Gtothedevice.Yourbrainknowsthat4Gisfasterthan3Gsoyoupaythepricefortheextraspeed.Thesamewillprobablybetruewhen5Ghitsthemarkets.TextTextWordsNotesDiscussionHome-4GLTELongTermEvolution--LTEsoundsbetter.Thisbuzzwordisaversionof4Gthatisfastbecomingthelatestadvertisedtechnologyandisgettingveryclosetothespeedsneededasthestandardsareset.WhenyoustarthearingaboutLTEAdvanced,thenwewillbetalkingabouttruefourthgenerationwirelesstechnologiesbecausetheyaretheonlytwoformatsrealizedbytheInternationalTelecommunicationsUnionasTrue4Gatthistime.Butforgetaboutthatbecause5Giscomingsoontoaphonenearyou.(Tobecontinued)

TextTextWordsNotesDiscussionHome(Continued)ThenthereisXLTE[2]whichisabandwidthchargerwithaminimumofdoublethebandwidthof4GLTEandisavailableanywheretheAWSspectrumisinitiated.Verizon,T-MobileandSprinthavealladvancedtotheLTEtechnologywitheachcarrieraddingtheirowncombinationofwirelesstechnologiestoenhancethespectrum.TextTextWordsNotesDiscussionHome-5GTherearerumorsof5Gbeingtestedalthoughthespecificationsof5Ghavenotbeenformallyclarified.Wecanexpectthatnewtechnologytoberolledoutaround2020butinthisfast-pacedworlditwillprobablybemuchsoonerthanthat.Seemslikealongwaysawaybuttimefliesandsowill5Gatspeedsof1-10Gbps.TextTextWordsNotesDiscussionHome2.Understanding4GTechnologyStandardsTheterm“4G”referencestoanewspeedstandardinInternetconnectivity,butwhatexactlydoesthetermmean?Whatis4G?TextTextWordsNotesDiscussionHomeMostusersarefamiliarwith“4G”standards,asmostsmartphonesusethiscommunicationsstandard.4Gsimplymeans“fourthgeneration”inreferencetotheevolutionofdatatransfertechnologies.Thefirstgenerationofmobiletechnology(1G)camein1981withanalogtransmission,andin1992was2Gappearedintheformofdigitalinformationexchange.3Gmadeitsdebutin2001,andincludedmulti-mediasupportalongwithapeaktransferrateofatleast200kilobitspersecond.True4Gsupportishere.Itisnosurprise,then,that4Gmeans“fourthgeneration”andrepresentsanumberofimprovementsoverthe3Gtechnology.TextTextWordsNotesDiscussionHome3.WhoSetsthe4GStandards4Gtechnologyismeanttoprovidewhatisknownas“ultra-broadband”accessformobiledevices,andtheInternationalTelecommunicationsUnion-Radiocommunicationssector(ITU-R)createdasetofstandardsthatnetworksmustmeetinordertobeconsidered4G,knownastheInternationalMobileTelecommunicationsAdvanced(IMT-Advanced)specification.TextTextWordsNotesDiscussionHome4.Whatarethe4GStandards?First,4GnetworksmustbebasedonanallInternetprotocol(IP)packetswitchinginsteadofcircuit-switchedtechnology,anduseOFMDAmulti-carriertransmissionmethodsorotherfrequency-domainequalization(FDE)methodsinsteadofcurrentspreadspectrumradiotechnology.Inaddition,peakdataratesfor4Gnetworksmustbecloseto100megabitspersecondforauseronahighlymobilenetworkand1gigabitpersecondforauserwithlocalwirelessaccessoranomadicconnection.True4Gmustalsobeabletooffersmoothhandoversacrossdifferingnetworkswithoutdatalossandprovidehighqualityofservicefornext-genmedia.TextTextWordsNotesDiscussionHomeOneofthemostimportantaspectsof4Gtechnologyistheeliminationofparallelcircuit-switchedandpacket-switchednetworknodesusingInternetProtocolversion6(IPv6).Thecurrentlyusedstandard,IPv4,hasafinitelimitationonthenumberofIPaddressesthatcanbeassignedtodevices,meaningduplicateaddressesmustbecreatedandreusedusingnetworkaddresstranslation(NAT),asolutionthatonlymaskstheprobleminsteadofdefinitivelysolvingit.IPv6providesamuchlargernumberofavailableaddresses,andwillbeinstrumentalinprovidingastreamlinedexperienceforusers.TextTextWordsNotesDiscussionHome5.UnderstandingLTETechnologyStandardsThemarketforwirelessdatatransferisquicklyevolvingasglobalratherthanlocalsolutionsarepursued–solutionsofferingrobustdatatransferrates,predictablespikesintrafficandareinteroperable.Oneofthefastest-growingstandardsinthecompetitionforownershipofthenewfourthgenerationor“4G”marketisLTEtechnology,whichpromisesanumberofimprovementsovercurrentmobileanddataterminalservice.TextTextWordsNotesDiscussionHomeLTEactuallystandsfor“longtermevolution”,anditsfullnameis3GPPLTE,withthe3GPPstandingforthe3rdGenerationPartnershipProject,whichhasbeendevelopingthetechnology'sreleasedocuments.Often,LTEismarketedas4Gtechnologybycompaniesthatpackageitaspartoftheirwirelessormobileservice,butthestandardisbetterthoughtofas“3.9G”asitdoesnotyetmeettherequirementssetoutbytheITU-Rfor4G,whichincludesminimumuploadanddownloadratesfornetworksanddefineshowconnectionsmustbeestablished.AnewversionofLTEtechnology,LTEAdvanced,doessatisfytherequirementsofatrue4Gnetworkandisexpectedwithinthenextyear.TextTextWordsNotesDiscussionHomeSo,whatexactlyisLTE?It'sbasedonGSM[3]/EDGEandUMTS/HSPAnetworktechnologies,andprovidesanincreasetobothcapacityandspeedusingnewtechniquesformodulation.Itprovidespeakdownloadratesof300megabitspersecond,uploadratesof75megabitspersecondandatransferlatencyoflessthanfivemilliseconds.Itcanalsomanagemulti-castandbroadcaststreamsandhandlequick-movingmobilephones.ItsEvolvedPacketCore(EPC),IP-basednetworkarchitecture,allowsforseamlesshandoversforvoiceanddatatooldermodelcelltowersthatuseGSM,UMTSorCDMA2000technology.Inaddition,itcanscalefrom1.4MHzto20MHzcarrierbandwidthsandsupportsbothtime-divisionandfrequencydivisionduplexing.Overall,thenewarchitectureofLTEtechnologymeansloweroperatingcostsalongwithgreateroveralldataandvoicecapacity.TextTextWordsNotesDiscussionHome6.Understanding5GTechnologyStandards5Gstandsforthefifthgenerationofwirelesstechnologiesanditwillbefasterthan4G.Thatisano-brainerbuthowmuchfasteristhequestion.Thedetailsareabitsketchyatthispointbutthespeedsaresupposedtobeupwardsof1to10Gbpscomparetothe4Gstandardswhichare100Mbpsupto1Gbps.Yeahalotfaster.Butwillthosespeedseverberealizedisanotherquestionthatwewillfindoutsometimearoundtheyear2020.Thatistheexpecteddateoftherollout.Iamfairlyconfidentthattheterm5Gwillbeusedlongbeforetheofficialrelease.Youwillbehearingtermslike;“ournew5Gnetwork”andthenewest5Gphoneisnowavailable”longbeforetrue5Gspeedsareactuallyachievedifthe4Grolloutisanexample.TextTextWordsNotesDiscussionHomeHowFastwill5GBe?ApictureisworthathousandwordsandthisonefromGSMAIntelligencesaysalot.5Gisgoingtobefast.Fastenoughforyou?ItissupposedtobefastenoughforeveryoneeverythingandtheIoT.TheInternetofThings.5Gusagegoeswaybeyondyoursmartphoneanddevices.Thiswillbewhatdrivesyourcars,itwillallowmachinestocommunicateandprettymuchanythingelsethatwillbenefitfrombeingconnected.TextTextWordsNotesDiscussionHomeFigure1:Maxim

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