LTE Test Case App Note

Application Note

LTE and EPC Test An Overview of Test Concepts and Tools for Trials Table o Contents Specicc LTE Test Speci Test Areas � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �3 Overview��������������������� Overview������������ ����������������� ����������������� ������������������ ������������������ ������������������ ����������������� ��������������3 ������3 Gainingdeeperinsights��� Gainingdeeper insights������������ ����������������� ����������������� ������������������ ������������������ ����������������� ����������������� ������������4 ���4 Performancetesting��������� Performancetesting 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������������������ ������������������ ���������������10 ������10 ValidatingLTEvoice ValidatingLTE voice�������� ����������������� ����������������� ����������������� ������������������ ������������������ ����������������� ���������������� ��������12 12 Signalingvalidation������������������������ Signalingvalidation��������������� ������������������ ������������������ ������������������ ����������������� ���������������� ��������13 13 VoiceQoSandQoE VoiceQoS andQoE(MOS) (MOS) �������� ����������������� ������������������ ������������������ ������������������ ����������������� ���������������� ��������13 13 TestingQoSandQoE TestingQoS andQoEofLTE ofLTEstreamingvideo������������������� streamingvideo���������������������������� ����������������� ����������������� �����������14 ��14 EvaluatingLTEMIMOand EvaluatingLTE MIMOandfrequency-selectivescheduling frequency-selectivescheduling �������� ����������������� ������������������ ������������������ ���������15 15 Testingnetworkcoverage������������������������ coverage��������������������������������� ������������������ ����������������� ����������������� ��������������16 �����16 TestingLTEhandover������������������ handover��������������������������� ������������������ ������������������ ������������������ ����������������� �������������16 �����16 ValidatingLTEbackhaul ValidatingLTE backhaul��������� ������������������ ������������������ ����������������� ����������������� ������������������ ������������������ ������������18 ���18 VerifyingLTEhandsetIOT VerifyingLTE handsetIOT����������������� �������������������������� ������������������ ������������������ ����������������� ����������������� �����������18 ��18 Validatingdeviceconfiguration����� Validatingdevice configuration������������� ����������������� ������������������ ������������������ ����������������� ����������������� �����������18 ��18

WEBSITE: www.jdsu.com/test

Application Note: LTE and EPC Test—An Test—An Overview of Test Concepts and Tools for Trials

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Appendix:: Outline for a Basic Phase 1 LTE Appendix LTE Test Test Plan � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 20 Overview��������������������� Overview������������ ����������������� ����������������� ������������������ ������������������ ������������������ ����������������� �������������20 �����20 Achievabledataratesandlatency:single-userthroughputforUL/DLandTCP/UDP��������������20 Achievabledata Achie vabledataratesandlatency:cellthroug ratesandlatency:cellthroughputandMUthroughputforUL/DLandTCP/UDP hputandMUthroughputforUL/DLandTCP/UDP���21 ���21 Achievabledataratesand Achievabledata ratesandlatency:latency latency:latency����������������� �������������������������� ������������������ ����������������� ���������������� ��������21 21 Intra-LTEmobility:mobility Intra-LTE mobility:mobilityandh andhandoverperformance andoverperformance ������� ���������������� ������������������ ������������������ ������������21 ���21 Achievabledataratesand Achievabledata ratesandlatency:applicationperformance latency:applicationperformance �������� ����������������� ������������������ ������������������ ���������22 22 Coverageandcapacityradio Coverageand capacityradiofeaturesefficiency featuresefficiencyandgain andgainassessment:link assessment:linkbudget budget �������� ����������������� ���������22 22 Coverageandcapacityradiofeaturesefficiencyandgainassessment:scheduler�������������������22 Evaluationofantennaconfiguration Evaluationof antennaconfigurationoptions����������������� options�������������������������� ����������������� ����������������� ��������������23 �����23 Self-configurationandself-organizingnetwork Self-configurationand self-organizingnetworkfeatures features �������� ����������������� ������������������ ������������������ ������������23 ���23 Evaluationoffrequencyr Evaluationof frequencyreuse:one euse:onedeploymentscenario�������������� deploymentscenario����������������������� ������������������ ���������������23 ������23 BasicQoS:user BasicQoS: userdifferentiationbetween differentiationbetweennon-GBR non-GBRuserswith userswithdifferentQCI���������������������� differentQCI����������������������24 24 BasicQoS:user-differentiationbetween BasicQoS: user-differentiationbetweenGBR GBRandnonandnon-GBRu GBRusers��������� sers������������������ ������������������ ������������24 ���24 Basicapplicationperformance:webbrowsing,streaming,voicecalls,e-mail,VPN,on-linegaming��25

References � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 26 EPSspecificationreferences EPSspecification references �������� ���������������� ����������������� ������������������ ������������������ ����������������� ����������������� �����������26 ��26 3GPPreferences��������������� 3GPPreferences������ ����������������� ����������������� ������������������ ������������������ ������������������ ����������������� �������������26 �����26 NGMNreference��������������������� NGMNreference������������ ������������������ ������������������ ����������������� ����������������� ������������������ ���������������28 ������28 ETSIreference����������������� ������������������������� ����������������� ������������������ ������������������ ������������������ ����������������� �������������28 �����28

Glossary � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 29

Application Note: LTE and EPC Test—An Test—An Overview of Test Concepts and Tools for Trials

3

Specifc LTE Test Areas Overview

Creatinganoverallframeworkforthetesting, Creatinganoverallframeworkfor thetesting,evaluation,andoptimizationof evaluation,andoptimizationofLTEand LTEandSAEis SAEisalarge alargeand and complextopic�Thisdocumentprovidesa complextopic�This documentprovidesastartingpointthat startingpointthatcoversthe coversthetopicat topicatarelativelyhigh arelativelyhighlevel� level� Lookingacrossthelifecycleofatechnologysuch Lookingacrossthelifecycleofa technologysuchasLTE/SAE, asLTE/SAE,thetools, thetools,processes,andmeasures processes,andmeasuresmustbe mustbe tailoredtosuitorganizationalprioritiesatspecifictimeswithinthelifecycle(Figure1)�JDSUprovides acost-effectivesetofsolutionsthatenablereusingassetsacrossthelifecycle�Thisensuresnotonly completecoveragebutalsothereuseofresultsandassets,leadingtoasolidreturnoninvestment(ROI)�

 Technology  Technology eld trials

Lab trials

Field trials and vendor evaluation

Friendly customer trials

Commercial launch

Optimzation and wider deployment

Figure 1. A simple model of the LTE deployment lifecycle

TheexampleslistedbelowaddressdifferentaspectsoftestingatvariousstagesintherolloutofLTE/ SAE�TheseareofferedasanoverviewofthemajorelementsoftheLTEdeploymentlifecycle� • Techno echnologyel logyeldtrials dtrials − EvaluatethetechnologyagainstNGMNor EvaluatethetechnologyagainstNGMNorotherindustryrequiremen otherindustryrequirements ts − Testandvalidatetechnologyimplementations − Adoptaprocessthatismoreopenthanfullyclosedbilateraleldtrials • Lab Labtes testin ting g − EvaluateeNodeBschedulingperformance − Evaluatesecurityandbillingpolicies − Evaluateserviceperformanceincontrolledenvir Evaluateserviceperformanceincontrolledenvironments onments − EvaluateUEperformance − EvaluateMIMOperformancegains • Fieldt Fieldtrialsa rialsandve ndvendor ndorevalua evaluation tion − Evaluateend-to-end(E2E) Evaluateend-to-end(E2E)performance performance − Evaluatenetwork Evaluatenetworkcoverage coverage − Evaluatecellandnodeperformanceunder Evaluatecellandnodeperformanceunderloadedconditions loadedconditions − Evaluateself-optimizingnetworkcapabilities − EvaluateIRA EvaluateIRATcapabilitiesandperformance Tcapabilitiesandperformance − PerformKPImonito PerformKPImonitoringandbenchmarking ringandbenchmarking

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• Friendlycustomertrials − Understandend-userQoE/QoS − Conrmhistorictroubleshootingcapabilities − TesthandsetIOT,conformanceandpre-conformance − Monitorhandsetperformance − Includetrending,statisticsandVIPreporting • Commerciallaunch − Performservice-andaccesstechnology-awaremonitoring − VerifyE2Evisibilityandtroubleshootingcapabilities − Validateandunderstandsubscriberbehavior − UnderstandoverallnetworkandIRAThandover(HO)performance − Includeintegrationwithnode-loggingcapabilities • Optimizationandwiderdeploymentphase − ValidateandensureSONcapabilitiesareworking − Locateareasforexpansion − Monitorbackhaulperformanceimpactonend-userQoE − Benchmarkserviceperformancebetweenmacroandfemtoroll-out Theremainderofthisdocumentfocusesonthe“fieldtrials”portionoftheprocess�Eachsection describesthetestcasesmostoperatorswillwanttoundertakeandalsooutlinesthetoolsthatwillensure effectiveperformanceofsuchtests�Itisassumedthatnotalloperatorswillperformallstepssowillneed tomatchthetestcases(andpossiblesolutions)touniqueneeds� Gaining deeper insights

Foryears,personnelfromacrossAgilentTechnologieshavebeen involvedwithtechnologystandardizationandtestdevelopmentfor LTEandSAE�Since2008,Agilenthasactivelyprovidedtoolstohelp developerstakeLTE/SAEforwardtothemarketplace�InApril2009,the companypublishedacomprehensivebookcalledLTEandtheEvolution to4GWireless:DesignandMeasurementChallenges(ISBN:978-0-47068261-6)�Thisresourcehasreceivedsignificantandwidespreadpositive feedbackfromthewirelessindustry�InMay2010,JDSUacquiredthe NetworkSolutionsDivisionfromAgilent�Withthisacquisition,several contributingauthorstothisLTEbook—includingtheauthorofthis applicationnote—transitionedfromAgilenttoJDSU�Thebookis  justoneexampleofhowAgilent—andnowJDSU—contributetothe overalllandscapeoftheLTEandSAEindustry�Asacompaniontothebook,thisapplicationnote containsrelevantreferencestotheLTEbook,whichcanbestudiedseparatelyinpursuitofadeeper understandingofthevarioustopicsandconceptsinvolvedinLTEtesting�

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Perormance testing

WithLTE,muchofthefocushasbeenonincreasingsystemperformanceinareassuchasend-user throughput,latency,andidle-to-activetransitions�Althoughtheseimprovements—alongwith significantlyimpressivesingle-userdatarates—areimportantformarketingreasons,inthemselves theyplayalimitedroleinhowrealuserswillutilizeadeployedLTEnetwork�Thus,measurementsare neededforbothsingle-userpeakratesandmulti-userthroughput�Inanalyzingmulti-userthroughput andoverallcellcapacity,itisimportanttounderstandtheimpactofacell’srealdistributionofusersas wellasthemobilityandusagepatternsofthoseusers� Single-user throughput testing  Intheory,single-userthroughputtestingisquitesimple�However,inrealityitcanprovetobequitetricky� Asanexample,thefirstaspectstounderstandare what to measure and how to benchmark the result � LookingatthepublicresultsoftheLTESAETrialInitiative(LSTI)ProofofConcept(PoC)group,it canbeseenthatpeakrateswillvaryfromafewhundredkilobitspersecondatthecelledgetoover 150Mbpsinverygoodradioconditions(forexample,ina20MHz2x2MIMOsystem)�Inpractice, measuringthiswiderangeofratescouldbeperformedwithadedicatedhardwaretrafficgenerator thatwillhaveguaranteedperformanceandwillproducetrafficpreciselyaccordingtoananticipated trafficprofile�Suchaprofilecouldincludevaryingdatarates,differenttypesoftraffic,anddelay characteristicssuchasjitter�Otheralternativesincludesoftware-basedtrafficgenerators(for example,iperf)orsimplygeneratingthetrafficfromexistingstandardapplicationserversusedfor FTPorvideostreaming� Ifasoftware-basedtrafficgeneratorisused,itisimportanttounderstandtheconditionsunderwhich itwilldeliverreliableresults�Ingeneral,currentlyavailablesoftware-basedtrafficgeneratorsproduce acorrectaveragethroughput;however,theinstantaneousvariationscouldbesignificant�Togenerate highrates,dedicatedCPUresourcesmustbeconsistentlyavailabletothegenerator�Shouldother processesstartonthetrafficPC,andthisisoftenthecasewithcertainoperatingsystems,theremay becomplicatedsideeffectsintheEPCortheeUTRANbecausebufferingmightoccurunexpectedly� Consequently,theremaybeagapinthegeneratedtrafficandthusnothingtotransferovertheair interfaceforagivenTTI� Ifnotmanagedproperly,theuseofanexistingapplicationserver(forexample,anFTPserver)to generatethetrafficcouldalsoproduceunexpectedsideeffects�Forexample,anFTPservernormally accessesafilefromatraditionalharddisk�Ifmultipleuserstrytodownloadthesamefileatthesame time,therecouldbeabottleneckcausedbytheFTPserverratherthantheLTEairinterface(ingood radioconditions)�ItispossibletosetupanFTPservertomanagethisifpropercareistakenandthe appropriatedisksystemisapplied;however,oversightsassimpleasanimproperlyconfigureddiskcan skewtheoverallresults� Whenitcomestomeasuringtheperformance,oneessentialruleofthumbistounderstandthebasic aspectsthatwillcontroltheresults�Forexample,anunderstandingoftheunderlyingradiolayer transportsettingsiscrucial�HARQprovidesanexample:ifHARQisnotenabled,thelinkwillactually deliverahigherthroughputingoodradioconditionscomparedtotimeswhenHARQisnotswitched on�Ontheotherhand,reliabletransportdependsonHARQbeingswitchedon�Ifnot,problemssuch asasignificantamountofTCPretransmissionwillcropup,leadingtoaverypooreffectivethroughput� EvenifHARQisswitchedon,theamountofHARQretransmissioncanbeconfigured�Settingthisto averylowvaluewillincreasetheinstantaneousthroughputbutwillleadtoapooreffectivethroughput undernon-idealradioconditions�

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Foradetailedunderstandingofbearerthroughput,measurementsshouldbemadeatdifferentlayers intheprotocolstack—MAClayer,IPlayerandUDPorTCPlayers—afterapplicableretransmissions� Duringthesemeasurements,itisimportanttounderstandandrecordtheactualsettingsthatwere configuredfortheMAClayerandtheTCPlayer,andifanyspecificserviceorapplicationlayersettings havebeenapplied(forexample,iftheapplicationusingTCPhadoneormultipleTCPflows)� InsomeveryspecificcasesitmaybeusefultomeasurethehighestpossiblebitratethattheLTEair interfacecandeliver�Forthismeasurement,therecommendedapproachistomeasurethelossless (forexample,zeropacket-lossthroughput)ofasustainedUDPstream�Insuchcases,thespecific MAClayersettingsshouldberecordedaswellastheUDPpacketsize�Itcouldaddsubstantialvalueto performanRFC2544testovertheLTEconnection;thiswillstepthroughseveraldifferentpacketsizes andthroughputratestolocatethelosslessthroughputforeachrelevantpacketsize� Tounderstandwhythroughputischangingindifferentenvironmentsatdifferenttimes,thebest approachistorecordasetofLTE-relevantparameterswhileperformingthethroughputtest�These parametersshouldincludetheinputstotheeNodeBschedulingdecisions(forexample,CQIforall oftheranks(widebandandsub-band),thePMI,andtherankindicator)andinformationaboutthe resultingeNodeBschedulingdecisions(forexample,selectedmodulationandcoding,MIMOmode, etc�)�Whentestinguplinkperformance,therelevantpower-controlinformationshouldalsobelogged� JDSUprovidesallofthetoolsandprocessesneededtoplan,perform,evaluateresults,andprovide reportsforsingle-andmulti-userthroughputtesting�ThisincludesbothtoolstogenerateE2Etraffic aswellastoolstologdatafromhandsetsandrelevantnetworkinterfaces�Fortestinginthefield,signal sourcesavailablefromothervendorsemulateuplinkinterferenceandloadingcausedbyusersinother cells�Becauseloadinghasasignificantimpactonthroughputratesitshouldbeincludedaspartofany realisticevaluation�ThegeneratedinterferenceshouldideallyberepresentativeofanLTEairinterface inbothULandDL�AlthoughwhitenoisewasacceptableforUMTS,whichusesanoise-likeCDMAair interface,itdoesnotrepresentthepowervariationsacrossfrequencyandtimethatcharacterizeLTE’s OFDMandSC-FDMAmodulationschemes�Rapidvariationsmaytrickschedulersintomakingeither optimisticorpessimisticpredictionsofthechannelconditionsandsubsequentmodulationandcoding schemethatcanbereliablytransmitted�JDSUtoolsprovidethemeanstoevaluatethisimpactbefore networksbecomeheavilyloaded� Cell performance verification with multi-user throughput testing  MeasuringtheperformanceofanLTEsysteminasingle-usercaseprovidesabasicunderstanding uponwhichamorerealisticanalysisofthemulti-usercasecanbeperformed�Itshouldbe understoodthat,inmanycases,single-userpeakthroughputperformancewillbemuchhigherthan eventheaggregatecellthroughputwithseveralusersactivelydownloading�Fromindustrystudies performedbyLSTIandothers,DLcellthroughputisexpectedtobearound35-40Mbps(assuming 20MHzwith2x2MIMO)with10usersspreadoverthecell,allwithfullbufferdownloadsanda proportionalfairscheduler� 1,2

1�eseexpectationsarerelativelyconsistentwithprevious3GPPsimulations� 2�eterm“fullbuer”referstotheideathattheeNodeBisconstantlyschedulingdatafromtheS1interface�ebuermustalwayscontain enoughdatatofullysaturatethelinkeveninthecaseofaperfectRFenvironmentandthehighestthroughoutrate�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Whenbasicmulti-usertestingisperformed,theresultsmayvarygreatly,spanningfromvalues belowtheanticipatednumberstoratesnearthesingle-userpeakperformance�Thereasonforthis widevariationisduetotwokeyfactors:theoverallbehavioroftheeNodeB’sschedulingandthe environmentforeachindividualuser�Itisthereforeimportanttosetupthetestinarepeatablewayto ensurethatresultsareusefulontheirownandcanbecomparedagainstsimilartestsineitheradjacent cellsinthesamenetworkorwithcellsthatusenetworkequipmentfromanothervendor� Theprocessofsettingupatesttoverifycellperformancewithmultipleusershastoomanystepsto presenthereindetail�Inoutlineform,herearethekeysteps: 1� Evaluatethedistributionofsignalqualityinthenetworkthroughexhaustivedriveorwalktesting tobuildaCDF� a� IftheCDFsfordifferentcellsaresignificantlydifferent,theendresultwillbesignificantlydifferent� b� Thedistributionwilldependonthetypeofterraincoveredandwherethewalkordrivetestis performed�Forexample,includingindoorlocationswillproducelowersignalqualitiesthan outdoor-onlydrivetesting� c� Itisexpectedthatroughly80percentoftheLTEdatatrafficwillbegeneratedindoors� 2�DistributetheUEsaccordingtothesignalqualityCDFtoobtainapropertracprole� a� ThechoiceofdistributionshouldmatchnotonlythemeasuredCDFbutalsotheanticipated distributionofrealusersintherealnetwork�Forexample,ifitisanticipatedthatseveralusersare locatedinagroupinapubliclocation(forexample,anairportorcafé)thenitisadvisabletoplace someoftheusersinsimilarpatterns� b� DifferentMIMOconditionsmightbestressedduetothistypeofdistribution(forexample ,multiusergainsfromMIMO)� 3�Intherealnetwork,locatetheusersaccordingtotheplanneddistribution� a� Notethatitwillbenearlyimpossibletogetanexactmatchsoitisimportanttoinsteadlocatethe usersinanareasimilartotheoneidentified�Makesurethattheactualradioconditionsofthe chosenlocationsareloggedandstoredforthecompletedurationofthetest� b� Forcasesinwhichsomeoftheuserswillbeinamovingenvironment,makesurethatthiscanbe managedinacontrolledway� 4�EnsureOCNGisenabledintheDLfortheadjacentcellstocreateDLloadinginthecell� 5�EnsurerealisticULloadingisgeneratedfromUEsinadjacentcells� 6�GeneratetractothetestUEsandensurethateachUEissetuptoreceiveortransmittracwith fullbuers� 7�Logalloftherelevantparametersasidentiedearlierincludingthelocation(latitudeand longitude)ofeachUE� a� Logallrelevanttrafficfromthenetworkinterfacestoensurethatfullbufferswerepresentforall UEsinallconditions� b� VerifythatallUEswereactiveandthattheindividualUEthroughputratesarerealisticcompared toexpectations� 8�CorrelatetheUE’sentireindividualthroughputforMAC,IP,andUDPorTCPlayers� a� IfoneorseveraloftheUEsweremoving,theaggregatedthroughputmaychangeovertime dependingontheschedulingandspecificradioperformanceofeachdevice’senvironment�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Itshouldbenotedthatthisisnotarealisticwaytotestacell’sactualperformance inarealnetwork scenariowhenbuffersarenotalwaysfull�Instead,itisatestofhowtheeNodeBwouldbehavein averyspecificscenario�Thiscouldnormallybeconsideredaworst-casescenarioforaspecific distributionofusers� Realistic multi-user throughput testing  Despitethecomplexity,therearestilllimitationsinmulti-usertestingthatusesfullbufferdownloads anduploads�Inarealistictrafficscenario,usersareexpectedtohaveburstytrafficprofiles,possibly comprisingHTTP,voice,FTP,IM,e-mail,etc�Inthefull-buffercase,userswithgoodconnections downloadmoredatathanuserswithlowdatarates,whichbiasesresults�Althoughthisispartlytrue, userstendtodomorewithafasterconnection—thefull-buffercaseisperhapstooextreme�The question,then,iswhatwouldbeamorerealistictrafficmodel?Woulditbevaluabletopursuethis testingand,ifso,whatistheaddedvalue?Theanswerdependsonwhichphaseofthetechnologythe specificoperatorisinatthetime�Iftheoperatorisabouttoperformvendorselection,thiscouldprove tobeanessentialtesttoensurethattheequipmentbehavesappropriatelyintermsofscheduling,ability todeliverthedesiredQoS,andoverallfairnesstothedifferentusers� ItisalsoimportanttounderstandthatdeliveringtheexpectedQoSorbeingabletoprovidefairness inthesystemisnotnecessarilyadifficulttaskforaneNodeB�Inpractice,thedifficultyistheabilityto delivertheexpectedQoSwithaminimumofoverheadfactorsthatimpacttheoverallcellcapacity� Thefollowingisaproposedtesttohighlightcertainpossibledeficienciesinasystem� 1�QoSoverheadprovisioninganalysis a� Setupastaticmulti-usercelldownloadwith6to10usersperformingfull-bufferdownloads� b� Measuretheoverallcellcapacity� c� Reassignoneuserasamobileuserwithafixed-rate UDPstreamwiththesamemegabit-persecondratethatwasachievedinthefull-bufferdownload� i� SettheQoSparametersforthisusertomatchthefixedrateoftheUDPstream� ii� Verifythatthethroughputrateisintherangeof2to5Mbps� d� Measuretheoverallcellcapacity� e� Movetheuserfrommediumtopoorradioconditioninfivestepsandrepeatthecell-cap acity measurementsforeachstep� f� Movetheusertothecelledgeforthespecificdataratethatwasprovisioned� g� Measuretheoverallcellcapacity� ComparethecellcapacityrstwithandthenwithouttheQoSprovisionedforthebandwidththat canbedeliveredwithoutanyactualimpactontheoverallcellcapacity�encompare,stepbystep, theoverallimpactofusermobilityoncellcapacityandguaranteedQoS� 2�Testtheimpactofrealistictracbehaviorontheoverallscheduling a� Setupagroupofusers(6to10)witharealistictrafficprofileforthetypeofusersenvisionedfor theLTEnetwork�Thefollowingareexamplesofusescenarios� i� Downloadfivewebpageswitha30-seconddelaybetweeneachdownload�Eachpage contains20objectsforatotalof1�4MBperpage� ii� Receiveane-mailmessagewithalarge(forexample,10MB)attachment�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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iii� Send10e-mailmessages,fourwith2-MBattachmentsandsixsmalloneswithonly50KBof dataineach� iv� ListentoInternetradio(256Kbps)�  v� PerformabackgroundFTPdownloadofsevenlargefiles(totalof100MB,similartoa monthlyoperatingsystemupdate)�  vi� MakeoneVoIPcallusing12�2KbpsonaguaranteedQoSbearer� Notethatthetestconditionsmustbesetupsuchthattheradiointerfacewillbecongestedin certainconditionsduringtestexecution�Usethepreviouslymeasuredanticipatedcellcapacity numberstoselectthecorrecttest-caseparameters� b� Thesequenceofeventsoccursinparallelforeachuser;however,theusersareseparatedintime by10secondseach� c� EachuserwouldbelocatedinaspecificradioenvironmentdefinedbytheCDFforthespecificcell� d� LetthetestruntocompletionwhileloggingalldatafromboththetraceUEsandthenetwork basedprobes�Ifpossible,alsologthedatafromtheLTEUuinterface� Thedatashouldthenbeanalyzedtorevealactualbehaviorduringcongestedconditions�One shouldspecificallystudytheimpactofthescheduleronboththeguaranteedQoStraffic(VoIP) andthestaticRTPstreamfortheInternetradiobecausethesetwoservicesarethemostlikely todegrade� Asimpleandbasicmeasureistobenchmarkthetotaltimeofcompletionforthetestsequence (excludingtheInternetradiostreamandtheVoIPsession,whichcouldrunindefinitely)�The minimumcompletiontimeshouldberelativelyeasytocalculatebasedonthepreviously measuredperformanceforthemulti-userandfull-bufferdownloadscenarios�Thedifference fromthisminimumtimeshouldbeanalyzedtounderstandtheoverallefficiencyofthesystem� Addingmobilitytothistestcasewouldallowforfurtheranalysis�However,itwouldprobablyadd somuchcomplexitythatitcouldnotbejustifiedasabasiccase� Allaspectsoftheschedulingandperformanceoftheradioenvironmentshouldbeanalyzedto understandtheefficiencyineachlayerandduringeachprocess�Thiswillalsohelprevealwhich conditionsleadtosuccessfulschedulingresultsandwhichcauseschedulingissues� JDSUcanprovidethetoolsandtheprocessestoexecuteandanalyzetheresultsfromthesetypesof tests�JDSUtoolscanhelpcharacterizethebehaviorandallowforbothcompetitivebenchmarkingand regressiontestingwhena“laundrylist”mustbemaintainedforaspecificsupplier� Idle-to-active transition times OneofthemainexpectationsofLTEistoprovidean“alwaysconnected”experienceforendusers�This isachievedinpartbyensuringaswifttransitionbetweentheidleandactivemodes�TheoverallRRC statemachinehasbeenoptimizedandthenumberofpossiblestateshasbeenminimizedtoensure reducedcomplexity,lowerpowerconsumption,andfastertransitiontimes� Tomeasuretheidle-to-activetransitiontimesonemustbeabletoeitherfullycontrolUEbehavior orbeabletologalloftheassociatedsignali ngtoensurethedataisavailabletobemeasuredfromthe overalltraffic� JDSUtoolscanmeasureidle-to-activetimeaswellasotherrelevanttransactionandproceduraltimes� Thesemeasurementscanbeperformedusingeitherdatafromatracemobilealoneordatacombined fromtheLTEandEPCnetworklinkstoenabletruecorrelatedE2Emeasurements�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Latency testing  Theoverallexperienceismorethanthespecificbandwidththatanendusercanreceiveandhow quicklythenetworkwillenableswitchingbetweentheidleandactivemodes�Theexperiencealso dependsontheE2ElatencyofapackettransitioningthroughthecompleteEPCandeUTRAN� KPI veriication and calculation

TheJDSUbookLTE and the Evolution to 4G Wireless: Design and Measurement Challengesincludes anextensivesectionaboutKPIs,thecalculationmethods,andtheoverallmethodology(pleasereferto Chapter6)�Asaresult,theKPImaterialcoveredhereiskepttoaminimum� Itisunfortunatethatthephrases“keyperformanceindicator”and“KPI”havebecomecommonly misunderstoodandmisused�Atthemostbasiclevel,aKPIisnothingmorethanastatisticora measurement�However,itisthetestobjectiveormarketrequirementforagivenservicethatallowsa particularstatisticormeasurementtobeconsideredasakeyindicatorofperformance� Eventheterm“performance”canmeanverydifferentthingsdependingonthetestingcontext�For example,serviceperformanceforVoIPmaybemeasuredintermsofjitter,latency,anddropped packets�NetworkperformancemaybemeasuredbythenumberconcurrentVoIPusersthatcanbe servedwithanacceptablelevelofjitter,latency,andpacketloss�Thus,whenmeasuringqualityor performance,oneofthekeychallengesisagreeingondefinitionsthatenableconsistentinterpretations ofresults� Accordingto3GPP,KPIsgenerallyfitintooneoffivecategories:accessibility,retainability, integrity,availability,andmobility�Thelistissometimesexpandedtoincludethecategoriesof utilizationandusability� 3GPPKPIstandardizationeffortsarelargelyfocusedonmeasurementsrelatedtotheenduser’s perceivedQoS�Thesemetricstendtobemoreoperator-centricastheyrelatespecificallytomeasuring theabilityofcustomerstoobtainandmaintainaconnectiontothenetworkandtherebymakeuseof oneormoreavailableservices� KPIsarebestunderstoodinthecontextoftheactualobjectiveofthemeasurement�Eachpartofthe networkhasdifferentresponsibilitiesassociatedwithdeliveringasingleservice�Therefore,LTEspecificKPIsfocusontheeUTRANitselfand,inmanycases,relyontheeNodeBtoactuallymeasure itsownperformance�OnechallengeforanNEMisdefiningawaytoverifythatKPIscalculatedbythe eNodeBarecorrect,especiallywhenrunningathighloadorfullcapacity�Anotherchallengeforboth NEMsandWSPsismakingtheshiftfromsimplylookingatKPIstotroubleshootingandidentifying therootcausesofproblems� ForeachKPIcategory,eachservicemayhaveadifferentQoSprofileorQCIlabel�Toidentifythe performanceofeachtypeofservicebeingaccessed,themeasurementsshouldbemadeonaper-QCI basis�AdditionalKPIsineachofthesecategoriesshouldbeconsideredinordertoevaluatetheend-toendusabilityandmanageabilityofaservice� Keyaspectsofawell-designedend-to-endtestsystemarethedatasourcesandthepossiblemonitoring pointsthatexistinanLTEandSAEnetwork�Someofthetopicsdiscussedherearealreadypartofthe industrystandards�Otherareasmayormaynotbepartoffuturestandardizationeffortsby3GPP,ETSI, orotherindustrybodies�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Fundamentaltothetopicofdatasourcesandmonitoringpointsisanunderstandingofmeasurement theory,basicphysicallaws,andhowtheLTE/SAEtechnologyworksandisdeployed�Considerthe followingexamplecommontobothLTE/SAEandUMTSinwhichtwoengineersneedtomeasurethe RRCconnectionsuccessratiointhenetwork� • erstengineer,whoisexperiencedindrivetesting,commissionsatargeteddrive-testcampaign, measuringtheRRCconnectionsetupsuccessratioforawidearea�Clearly,thenumberof measurementpointsisdirectlyrelatedtothedurationofthetestingandthenumberofactual attemptsperunitoftime�Forthisexample,theengineerconcludedthattheRRCconnection successratiowas98�5percent� • esecondengineerisaccustomedtonetworkcountersandlink-monitoringtools�Asaresult, heextractslogsfromthesystem�isprovideshimwithareportofalloftheRRCconnection attemptsforthefullnetwork;hismeasuredRRCconnectionsuccessratiois99�5percent� Whyisthereadifferenceofnearlyonefullpercentagepoint?Theanswerisfundamentaltotherestof thisdiscussion� Thedifferenceintheresultsisnotduetoflawsinthedatasource,beitthedrivetest,thenetwork counters,orthelink-monitoringtools�Thedisparityiscausedbythetwoengineersmeasuringdifferent networkproceduresfromdifferentangles� • edrive-testmethodanalyzesnetworkperformanceasseenfromasinglehandsetatspecic physicalpointsinthenetworkatdistinctpointsintime� • enetworkcountersandlink-monitoringtoolsrecordallofthetracandalloftheoccurrences ofsignalingandusertractheyaredesignedtomonitor�isisadierentframeofreference:it analyzesnetworkperformanceasseenonthenetworkandatthenetworkmonitoringpoints� Differencesbegintoaccumulateifanydrive-testlocationsarewelloutsidetheactual,andpotentially, intendednetworkcoveragearea�Asaresult,RRCconnectionrequestsmadeoutsideofthenetwork coverageareawillberecordedbythedrive-testsystembutnotbythenetworkcountersorlinkmonitoringsolutions�Thishighlightsakeypoint:anextensivedrive-testcampaignprovidesadditional informationbeyondwhatnetworkcountersorlink-monitoringtoolscanprovide� Intheoptimizationcommunity,itisgenerallyagreedthatKPIsshouldbecomparedtoeachotheronly whentheyarederivedfromthesamedatasourceorwhentheyarenormalizedtoremoveanybiasdue tomethodorsource�Thisisespeciallytrueifcomparisonsshowunexpectedresults�Today,thelackof propercomparisonsisoneofthelargestcontributorstounsoundoptimizationdecisionsinthemobile industry�Validcomparisonsandmeaningfuloptimizationcanbeensuredonlyifastringentand coherentagreementondatasourcesandmonitoringpointshasbeensettledinadvance� 3 WhetherengagedintheR&Dprocessortheoptimizationphase,onemustoftenchoosebetween severaldifferentstrategieswhendevelopinganLTEtestplan�Selectingthemostcost-effectiveand results-effectivestrategyisoneofthemostimportantdecisionstobemadeearlyineachphaseofthe work�Onceastrategyisselected,theboundaryconditionsofitsapplicabilitymustbeestablished�Itis importanttonotethatastrategythatisappropriateforonephaseoftheworkprobablyhassignificant shortcomingsinanyotherphase�Inotherwords,itisseldomagoodideatousethesamefundamental KPIsbecausethedatasourceswillprovidedifferentresultsindifferentphasesofanetwork’s deploymentandmaintenance�

3�Pleasenotethatthisissimplyamatteroffundamentalmeasurementtheory�Itisnotintendedtobeadiscussionaboutthepotentialriskof resultsbeingincorrectduetoacertainmeasurementtoolnotworkingasdened�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Toillustratethisidea,consideracaseinwhichQoSiscontrastedwithQoE�Monitoringtheend-user IPtrafficonamobilenetworkprovidesafullanddetailedunderstandingofthetrafficflows(TCPor UDP),theapplications(voice,video,HTTP,e-mail,etc�),andpotentiallyperformance�Somebelieve thatthemonitoringofonlytheUDPorTCPflowswillprovideenoughinformationabouttheend-user QoStobeabletodeduceagoodapproximationoftheend-userQoE�Asthefollowingscenarioshows, thisisnotthecaseforapplicationssuchasstreamingvideo� • Auseriswatchingstreamingvideoonhishandset,buttheradioqualityisnotsucienttodeliver thefullbandwidthovertheairinterface�WhentheUDPstreamismeasuredinthecorenetwork, nodegradationoftheRTP/UDPstreamisobserved�reeotherlocationsprovideabetterplaceto observethedegradation:ontheairinterface,ontheuser’shandset,orbetweenthetwoendpoints oftheRLCentity(intheUTRANbetweentheUEandtheRNCorintheLTEeUTRANbetween theUEandtheeNodeB)�enetworkmonitoringtoolinthecorewouldreportahighandstable bitrate(goodQoS);however,theenduserwouldreportapoorQoE� • Shiingthescenarios,assumethattheenduser’sapplicationisquality-awareand,duetotheradio conditions,signalsthatthevideostreamingservershouldchangethebitrateofitscodec�When thisnewRTP/UDPbitstreamappearsonthenetwork,thenetworkmonitoringtoolwillassociate thechangewithalowerQoSstreambecauseithasalowerbitrate�Ontheotherhand,theradio conditionsaregoodenoughtodeliverthisadaptedbitstream,andtheenduserQoEhasnowincreased� ThisscenarioshowsthatthecrucialelementintheQoEisnotthebitratemeasuredinthecorenetwork, butrathertheend-to-endabilitytodeliveraspecificservicetotheenduser�Theapplicationdomain will,inthiscase,ensurethatthebestpossibleQoEisachieved�Therefore,themonitoringtoolmustbe application-awaretodelivercorrectQoSmeasurementsthatleadtothecorrectestimationofend-userQoE� Validating LTE voice

Oneoftheto-be-defineditemsfortheEPSishowcircuit-switchedservicessuchasvoice,CSUDIvideo, SMS,LCS,andUSSDwillbemanaged�Fouralternativesarecommonlyconsidered� • Circuit-switchedfallback(CSFB) • VoiceoverLTEgenericaccess(VoLGA) • VoiceoverIMS(VoIMS) • Proprietaryoptions CSFBandVoLGAarebothstandardizedandcouldbereadilyimplemented�VoIMSislikelytofollow andisanticipatedtobeawidespread,long-termsolution�Amongthese,CSfallbackinEPSisdescribed indetailbelow;theotheroptionsarecoveredinbrief� Anotheraspectthatisnotyetspecifiedin3GPPR8istheuseofavoicecodec�Severaldifferentoptions areathand;however,duetoalackofagreement,thispartofthestandardizationmightbedelayeduntil R10�Onekeyreasonforthedelayisthelackofclarityontheobjective:shouldthequalitybeimproved orshouldthecapacitybeimprovedbythechoiceofcodec?Itislikelythatachoiceofcodecforinitial EPSdeploymentswillbebasedonamutualbilateralagreementbetweentheUEvendors,theoperators, andtheEPSprovider�ItwouldnotbeasurpriseifAMRandAMR-WBwereusedinitially� ItiscrucialtounderstandthattheITUhasalreadymovedaheadwiththedefinitionoftheG718codec� G�718isbuiltontheAMR-WBfoundationand,forthemostpart,providesthequalityofAMR-WB at12�65KbpsonthesamecapacityasAMR7�95Kbps�Overall,thismeansthatG�718providesa57 percentincreaseincapacitywithaverylimitedimpactonspeechdelay�Adetaileddescriptionis outsidethescopeofthispapersothereaderisencouragedtostudyITU-TRec�G�718infulltofurther understandthistopic�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Signaling validation Figure2isatypicalexampleofanIMScallflowforLTEinteractingwiththeSS7network�Aswillbe shown,thisisfarfrom“onlySIP”andsomeofthecriticalaspectscannoteasilybeseeninthissimplified  view�Oneexampleisthelackofvisibilityintothechoiceofthebearersthathavebeensetupandhow theymaptoacertainQCI,etc� Anyshort-termanalysisofavoice-over-LTEimplementationwillmostprobablybeimpactedbyone orseveralshortcutseveniftheintentionistobestandardscompliant�Thisshouldbeconsideredwhen performinganalysisanddrawingconclusions�KeyaspectstoconsideraretheusageofROHCforthe airinterface;theusageofacodecforE2EspeechandtheintegrationofapagingprocedurewhentheUE isinidlemode;and,howthemobilitybetweenaccesstechnologieswouldbemanaged�

Originating UE

eNB

MME

Core IMS

 Terminating UE

PSTN

Delay for RACH scheduling period Rach preamble  TA + Scheduling RRC Connection Request     E     V     I     T     C     A     O     T     E     L     D     I

RRC Connection Setup RRC Connection Setup complete + NAS service request

Security Mode Command + RRC Connection Reconguration

Connection Request Connection Setup

RRC Connection Reconguration complete SIP INVITE SIP 183 Session Progress     P     U     T     E     S     L     L     A     C

IAM

SIP PRACK 

IAM

SIP 200 OK  SIP UPDATE SIP 200 OK 

SIP 180 Ringing

COT ACM/CPG

COT ACM/CPG

Figure 2. Typical IMS call ow for LTE interacting with SS7

Voice QoS and QoE (MOS) VoiceQoSandtheresultingQoEisatopicofmanygoodpublicationsandthusthissectionwillnotgo intotoomanydetails� Overall,onemustbecarefulaboutwhatistestedunderwhichconditions,andonemustbeawareofthe governingfactorsthatcontroltheoutcome�Ifacertainvoiceserviceistestedwithabearerdeliveringa specificQoS,thentheresultingvoicequalitywillbelimitedbythequalitydeliveredbythebearer�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Whilethissoundssimpleintheory,itcausessignificantpracticalconcernsinalmostallnew technologiesbeforetheE2Estructureiswellunderstood�InUMTS,voicewasnormallydelivered usingaradiolinkwithaone-percentBLERtarget�Certainimplementationsusedonepercentasa minimumqualitytargetbutover-deliveredonqualityifandwhenresourceswereavailable�This meantthatcomparingasituationinwhichtheBLERwasalwaysheldattheconfiguredBLERtarget (regardlessofavailableresources)andBLERwasadjustedtodeliverthebestpossibleservicewithout causingdegradationforothers,theresultsinanunloadednetworkwouldalwaysfavorthe“flexible” implementation�Thisisnotalwaystheintendedtestobjectandthusthevalueofvoice-qualitytesting canbedegradedorworse,beconsidereduseless�Therefore,itiscriticaltounderstandtheunderlying conditionsthatwillimpactvoiceserviceandtoeithercontrolthesefullyorrecordonlythose parametersused�Thiswillensurefaircomparisonswhenbenchmarkingaresulteitherovertimeor betweenimplementations� JDSUsuppliestoolsthatcanperformE2Evoice-qualitytestingandalsobenchmarkvoicequality passivelyinsidethenetwork(Figure3)� JDSU VoIP Office End

JDSU J7830A Signaling Analyzer and J6900A Triple Play Analyzer 

EPC

Serving/PDN GW Element Management System / Network Management System JDSU J6804A DNA HD eNB

eNB

UE JDSU E6474A NiXt

UE JDSU E6474A NiXt

Figure 3. Network architecture for E2E voice-quality testing

Testing QoS and QoE o LTE streaming video

QoSandQoEmonitoringofavideoserviceisdirectlyanalogoustotheearlierdiscussionofKPIs�In short,allofthesamemethodsandissuesidentifiedintheKPIsectionapplytothesemeasurements� Ratherthanrepeatingthatmaterial,pleasereferbacktotheearlierdiscussion� Thereisonekeypointtoadd:understandingvideoQoSandtheresultingQoEshouldbedoneacrossall relevantaspectsoftheLTEandEPC�ThismeansthatonecannotonlyidentifytheactualQoSatapoint butcanalsoensuretheserviceupstreamfromthispointifthetrafficflowisgoodatthemonitored location�Ontheotherhand,ifthetrafficflowispooratthemonitoringlocation,thenafurther investigationupstreamshouldbeperformed�Notethatinmanycasestheclientcanusejitterbuffersto compensateforacertainamountandtypeofQoSimpairments�Thus,adegradedQoSdoesnotalways leadtothedegradationofQoE�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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JDSUprovidesalloftherelevanttoolstomonitorvideoQoSandQoEfromeitherapassiveperspective orfromanactiveperspective(Figure4)�SupportisprovidedforbothstandardIPTVandforMSTV�

Evolved UTRAN (E-UTRAN)

Evolved Packet Core (EPC)

Core, Services, IMS

S-GW P-GW

Internet

Uu

UE’s

Evolved Node B

PCRF MME

HSS

CSCF

MRF

Figure 4. Tools for monitoring end-to-end LTE QoS and QoE ( VoIP, IPTV, data)

Evaluating LTE MIMO and requency-selective scheduling

ComparedtoHSPAsystems,muchofthevalueinLTEcomesfromtheeffectiveusageofbothMIMO andfrequency-selectivescheduling(FSS)�Inmanyaspectsthesearetechnologiesthathaveyettobe provedintermsofaddingrealtangiblevaluetothecustomerinafieldenvironment�Theirrealvalue dependsonthreethings:theactualdeploymentscenario;theoveralltrafficmodeling;and,thespecific implementationandconfigurationofthesystem� AfeaturesuchasFSSmakesittheoreticallypossibletoaddsignificantperformancetothesystem�In practice,however,performanceislimitedbythealgorithmusedtocontrolscheduling�Thisisdue tooperationaltradeoffssuchasreducingsignificantuplinktrafficforsub-bandCQIreporting,or technicalfactorssuchasthepracticalavailablecomputationalperformanceintheeNodeB� AsfarasMIMOisconcerned,itshouldbeunderstoodthatMIMOusageorthemeasurements leadingtoaspecificMIMOconfigurationforspecifictransmissionstoauserduringaspecificTTIis typicallynotastaticbehavior�What’smore,anyexpectationthatMIMOcanbecontrolled,modeled, orunderstoodfromoneorafewmeasurementsistypicallyunrealistic�Asaresult,itisimportantto identifytwokeyelements:thoseaspectsofthetechnologythatshouldbeevaluatedfromastatistical behaviorpointofview;and,thoseparametersthatcanbeanalyzedfromasinglediscretemeasurement withoutlookingatalargersample� ItisvitaltounderstandandcharacterizetheactualbehaviorofbothMIMOandFSStoensurethe properdimensioningofthecells,thebackhaul,andtheQoSprovisioning�Thestatisticalnatureof MIMOandFSScanbewellunderstoodonadetailedTTIlevelonlyiftherighttoolsandprocessare applied�ThesecapabilitiesareallavailableusingJDSUtoolsandmethods�Thetoolsallowadetailed analysisandcharacterization,enablingaclearunderstandingofactualbehavior�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Testing network coverage

Duringnetworkplanning,modelingisperformedandassumptionsaremade�Iftheseareatall inaccurate,theundesirableconsequencesincludeeitherunplannedcoverageholesorunwantedsignal leakageintoadjacentcells�Earlyintheplanningandtuningprocess,aclearunderstandingofactual networkcoverageversustheplannednetworklayoutenablestheplanningandengineeringteamto developastrongmethodologythatallowsforverycost-effectivenetworkdeploymentandtuning�Early  verificationofthecoveragewillallowcreationofaCDFofthenetworkperformanceandallowfor propertestingofcellperformance� JDSUprovidesdetailedRFcoveragemeasurementsincludingRSSI,RSRP,RSRQ,andRS_CINR� Thesecapabilitiescaneffectivelycoveralargenumberofbandsinverycomplexnetworktopologies� Theresultsfromthemeasurementscanbepost-processedwitheithercustomsoftwareoranyofthe industry-standardpost-processingapplications� Testing LTE handover

CoveragetestingiscloselylinkedtothecharacterizationofHOvalidationandperformance�Tofully graspHOperformance,onehastofirststudyandunderstandtheoverallproceduresandprocessesthat underliethehandoverinLTE�Asiswidelyunderstood,nosofthandoverispresentinLTE�Asaresult,the handoverisalwaysahard“breakbeforemake”transition�Theresultingimpactonend-userQoEmust beunderstoodandoptimized�Itisalsoimportanttounderstandthehandover’soverheadimpacton theeNodeBbecauseLTEhandoverscanbeusedtoproactivelymanageserviceloadinginaspecificarea� Severaldifferenttypesofhandoversarepresent:thosebetweencellsinthesameeNodeB;thosebetween cellsindifferenteNodeBswithoutanyX2dataforwarding;and,thoseinwhichX2dataforwarding isensuringaminimuminterruptionofdatatraffic�ItiscommonlyunderstoodthattheX2data forwardingfeaturemightbeimplementedinlaterreleasesoftheeUTRANsoftware;however,some  vendorsmightmakethiscapabilityavailableearlyinthelifecycle� AUEcannormallydiscriminatebetweenthetypesofhandoversbymonitoringtheSFNaroundtheHO timeandcheckiftheSFNisjumpingoriscontinuous� Figure5isagoodexampleofahandoffbetweentwocellsinasingleeNodeB�Theplotshowsthatthe BLERisincreasingthemomentsbeforetheHOandthatthisresultsindegradedthroughputonthe MAClayer�AftertheHOisperformed(forexample,anRRCconnectionreconfiguration),MAClayer throughputisincreasedandnoBLERisreported�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Figure 5. MAC throughput (green line) sags before an RRC event but recovers immediately after.

Followingthisfromasignalingperspective,thecalltrace(Figure6)revealstheresultingHO interruptiontime,whichisontheorderof12to35ms�Notethatthisanalysisrequiresaccesstoboth theprotocollogsfromtheUE(orfromapassiveUuprobeorfromaeNodeBfeed)withthosefromthe networklinks(forexample,S1,X2,etc�)�

Figure 6. A call trace can reveal the resulting HO interruption time

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Asinallmobiletechnologies,itisrelativelystraightforwardtoachievesuccessfulhandovers�However, achievinganoptimizednetworkwithoptimizedhandoversrequiresgreatinsightandtremendousskill intheartofoptimization� Validating LTE backhaul

LTEoffersgreatlyincreasedbandwidthtotheenduser�Inturn,itisveryimportantthatthisbandwidth capabilityisavailablethrougheverypartofthenetwork�Oneofthebigareasoffocusforthisisthe mobilebackhaulnetwork,typicallyEthernet,betweenthecellsite(eNodeB)andthecorenetwork� InLTEfieldtrialswehavewitnessedtodate,thewirelessbackhaulnetworkisbroughton-lineprior toimplementationoftheLTE-specifictestcases�CommissioningtheEthernetbackhaulquicklyand easilyisvitaltokeepinganLTEfieldtrialonschedule�TheJDSUNetCompleteServiceAssurance SolutionforWirelessBackhaulverifiesEthernetserviceoperationtotrialcellsitesinadvanceofthe LTEtrialexecution�AdherencetoRFC-2544standardsismaintainedwithcost-savingderivedthrough automationandefficientdeploymentoftechniciansevenacrossmultiplecellsites�However,since suchtestingisnotuniquetoanLTEfieldtrial,itisbeyondthescopeofthisapplicationnote�General informationisavailablesuchastheIETF’sRFC2544(1999),theIEEE,andtheITUwhichdefinetest andperformancemonitoringmethodologiesforEthernetnetworkinterfacedevices� Veriying LTE handset IOT

ForeachoperatorintheearlyphasesofbringingLTEtomarket,itisessentialtoensureproper interoperabilityofLTEhandsetsordatacards�Ofcourse,theseareearlydevicesthatwillcontinue toevolverapidlyovertime�Consequently,itisimportanttounderstandthecapabilitiesandensure interoperabilitybetweenthehandsetandtherelevantnetworkelements�Itwillnotbepossibleto simplyrelyonpre-conformanceorconformancetestresultsbecausethesewillseldomreflectactual userbehaviororissuesfoundintheearlyphasesofnetworkdeployment� IndustryforumssuchasLSTIhavedefinedaminimumfeaturesetandacorrespondingIoDTand IOTtestplan�TheseareavailableonlytoLSTImembersandmaybeusedonlyforLSTIpurposes�Asa result,non-membersmustrelyonothermeanstosecurehandsetinteroperability�AsanLSTImember, AgilenthasmadesignificantcontributionstotheIoDTandIOTphases�Throughthisexperience personnelinbothAgilentandJDSUarebetterabletocontributeeffectivelytothewiderindustry� JDSUprovidesmonitoringtoolssuchastheSignalingAnalyzerthatprovidethecapabilitytoanalyze andcorrelateinformationfromeachinterfaceandhighlightanydiscrepanciesversustheanticipated behavioronasignalinglevel�TheJDSUNiXTapplicationcanactivelystimulateahandsettoexecute differentapplicationsandtasks�ThiscorrelatestocontroloftherelevantRFparameters(forexample, fading,MIMOprofiles,etc�)andaneffectiveLTEhandsetinteroperabilityenvironmentcanbe provided�Ifappropriatelyandeffectivelyautomated,thiswillensurethatcost-effectiveandreliable testingisperformed,therebymaximizingassetutilization� Validating device coniguration

OnepartofLTEisyettobefullystandardizedandwidelyagreedupon:theeffectiveperformanceof deviceconfiguration�Evenifsignificantinteroperabilitytestinghasbeenperformed,anyoperator launchinganLTEserviceearlywillberequiredtoremotelyupdatehandsetsandparameterssuchas networksettings,software,orotherrelevantparametersduringoperationofthenetwork� 4 4�ManyofthetraditionalOTAsystemsarebasedonshortmessageservices(SMS)thatarenoteasilysuppliedinanLTEenvironmentwithout theuseofeitherCSFBIMSorVoLGA,bothofwhicharerelativelycomplexanderror-pronetechnologies�

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Itisessentialtoprovidefullvisibilityintodevicebehaviorduringpre-configuration,configuration, andpost-configurationphases—andtocomprehendthefullE2Esignalingneededtodeliverthe configurationenvironment�WithJDSUtools,thepre-configurationstatecanbeanalyzedboth qualitatively(forexample,theperformanceofalloperationalservices)andinsimplego/no-gotesting (whichservicesworkordon’twork)�Specificnetworkbehaviorsthatidentifyincorrectlyconfigured devicescanbeanalyzedanddocumentedtobeusedinsubsequentnetwork-widemonitoringsystems� Duringtheconfigurationprocedure,differenttypesofpositiveandnegativetestingcanbeperformed tostimulateerrorconditionsandtoprovethattheconfigurationissuccessfulifcertainconditionsare met�Thenegativeconditionsareespeciallycriticalbecauseitisoftendifficulttoevaluatethestateofan end-userdeviceinarealnetwork�

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Appendix: Outline or a Basic Phase 1 LTE Test Plan Overview

Thissectioncontainsabasicsetoftestcasesthatcanbeusedintwoways:toevaluateLTEasa technology;and,toassessthebasicperformanceofLTEinfrastructurevendors� Thebasictestplandescribedhereiswell-alignedwiththethinkingofmostinfrastructurevendors�It isalsoconsistentwiththeirdetailedtestplans�Asaresult,thissectioncanbeusefultooperatorstoo� Theycanusethisplanwhenaskingvendorstocreateadetailedoutlinethatspellsouthowtestingwill beconducted�Theoperatorcouldthenvalidatethatthedetailedtestplanmeetstheintentionand basicexpectationsoftheplan�Theoveralltestexecution,datacollection,analysis,andreportingcanbe managedwithintegrity,ensuringavalidevaluation� Subsequentphasesofatestplancanbeprovidedthatwillallowtheoperatortomovetowardvendor selectionandnetworkroll-out� Thesuggestedtestplanhaseightmajorsections� • Achievabledataratesandlatency:single-userthroughputforUL/DLandTCP/UDP • Intra-LTEmobility  • Coverageandcapacity  • Evaluationofantennacongurationoptions • Self-congurationandself-organizingnetworkfeatures • Evaluationoffrequencyreuse • BasicQoS • Basicapplicationperformance Below,“Achievabledataratesandlatency”hasfoursubsectionsand“Coverageandcapacity”hastwo� Eachofthe13totalentriespresentsabasictestoverviewthatcanbeeasilyleveragedintoatestplan� Achievable data rates and latency: single-user throughput or UL/DL and TCP/UDP

Basic test overview  • Evaluatesingle-userthroughputacrossarangeofradioconditions�GenerateULandDLloadingof 70percentfromadjacentcells� • PerformseparateULandDLthroughputtestsindividuallywithTCPandUDP�Measureaverage throughputfor30secondsduringstationaryconditions�eTCPandUDPtestsshouldmeasure losslessthroughputratherthanrawthroughput� • Logallappropriateparametersandconditionsincludingfulltracesofthecontrolanduserplanes fromthenetworkandUEsides� • Providerawandnormalizedresultsaccordingtothecommontestdescription�

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Achievable data rates and latency: cell throughput and MU throughput or UL/DL and TCP/UDP

Basic test overview  • GenerateaCDFofthecellaccordingtothecommontestdescription�Place10UEsaccordingto theCDFdistribution� • Verifyplacementofthe10UEsinappropriateandrepresentativelocations� • GenerateULandDLloadingof70percentfromadjacentcells� • PerformseparateULandDLthroughputtestsindividuallywithTCPandUDP�Measureaverage throughputfor30secondsduringstationaryconditions�eTCPandUDPtestsshouldmeasure losslessthroughputratherthanrawthroughput� • Logallappropriateparametersandconditionsincludingfulltracesofthecontrolanduserplanes fromthenetworkandUEsides� • Providerawresultsandnormalizedresultsaccordingtothecommontestdescription� Achievable data rates and latency: latency

Basic test overview  • Evaluatetheend-to-endlatencyinarangeofradioconditionsandloadingscenarios� • No-loadscenario − Performend-to-pinginarangeofradioconditionsforaminimumof100samplesperlocation andpacketsize(32,1000,1500bytes)� • With-loadscenario − GenerateULandDLloadingof70percentfromadjacentcells� − Generatesame-cellDLloadfromoneUEingoodradioconditionswithfullUDPdownload� − Generatesame-cellULloadfrom1UEinpoorradioconditionswithfullUDPupload� − Performend-to-endping(32,1000,1500bytes)inarangeofradioconditionsforaminimumof 100samplesperlocationandpacketsize� • Logallappropriateparametersandconditionsincludingfulltracesofcontrolanduserplanefrom thenetworkandUEsides� • ProvideRANandEPClatencyand,ifrelevant,thebackhaultransmissionlatency� • Providerawresultsplusminimum,maximumandaveragevaluesforeachradioconditionand packetsize� Intra-LTE mobility: mobility and handover perormance

Basic test overview  • TestandcompareresultsforhandoverbasedonbothS1aloneandonX2forwarding;testsamecell loadedandunloaded� − Samemethodologyforboth(S1andX2)testcases º Repeattestforatleast20HOofeachtype� º PerformthetestwithDLandULTCPandUDPtracsubsequently� º MeasureandreportHOsuccessrate� º MeasureandreportcontrolplaneHOtime� º MeasureandreportuserplaneHOinterruptiontimeandpacketloss�

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• Logallappropriateparametersandconditionsincludingfulltracesofcontrolanduserplanefrom thenetworkandUEsides� • ForloadedHOperformance,testaddtwoUEsingoodradioconditionsinbothcellsperforming full-buerDLandUL� • Othercellloadshouldbe70percentinDL�Inthemobilitycase,notethatULloadingisnot requiredduetopracticalissues� Achievable data rates and latency: application perormance

Basic test overview  • Fromidlemode,connectanddownloadtheCopernicuswebsite(seecommontestdescription)and measurethedownloadtimeinarangeofradioconditions�Aminimumofverepetitionsateach locationisrequired�Aminimumofve(10isrecommended)dierentradioconditionsshouldbe coveredfromgoodradioconditionstocell-edgeconditions� • eothercellloadshouldbe70percentinULandDL� • Logallappropriateparametersandconditionsincludingfulltracesofthecontrolanduserplanes fromthenetworkandUEsides� Coverage and capacity radio eatures eiciency and gain assessment: link budget

Basic test overview  • Testrstinstaticlocations: − eUEislocatedclosetothecellcenter�AUDPDLtransferwithfullbuerisinitiated� − eusermovesawayfromthebasestation,sopathlossincreases�Repeatthemeasurementsat thenewlocation� − isisrepeatedforatleast10dierentlocationsacrossthecell�Amajorityofthelocations shouldbeinpoorradioconditions;continueuntilcoverageislost� • Repeatthesametestwhileinmobileconditions:drivefromcellcentertocelledgeandrepeat severaltimes� • Logallappropriateparametersandconditionsincludingfulltracesofcontrolanduserplanesfrom thenetworkandUEsides� Coverage and capacity radio eatures eiciency and gain assessment: scheduler

Basic test overview  • LocatefourUEsingoodradioconditionsascloseaspossibletoequalradioconditions�Ensurethat allUEshavethesamepriorityandQoSsettings� • SetupDLloadingofUDPwiththefollowingtraccharacteristics:UE1=X;UE2=2*X;UE3=3*X; UE4=4*X�EnsureXischosensothattheaggregatedthroughputoftheusersexceedsthecellcapacity� • Measuretheresultingbehavior� • LocatetheUEsatfourdierentlocationsandgeneratethesameUDPstreamthroughputtoeach UE�Ensureaggregatedthroughputoftheusersexceedsthecellcapacity� • Measuretheresultingbehavior� − Logallappropriateparametersandconditionsincludingfulltracesofthecontrolanduser planesfromthenetworkandUEsides�

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Evaluation o antenna coniguration options

Basic test overview  • Performthesingle-userthroughputtestcaseandthemultiusercellcapacitytestcasewiththe followingantennacongurations: − SIMO − 2x2MIMO − 4x4MIMO(Optional:Performifpossibleforthevendor) Sel-coniguration and sel-organizing network eatures

Basic test overview  • EnsureatleasttwoeNodeBsareoperationalandnoneighborsexistinthetargetcell� • VerifyintheO&MsystemthatnoneighborsorX2interfacesarecongured� • ActivateANRineNodeB� • TurnontheUEinacellwherenoneighborsaredened�AerUEreportingofsignalstrengthsof surroundingsectors,theANRfunctionshalladdneighborstotheneighborlist� • Performahandover� • VerifyintheO&MsystemthatallcorrectneighborsandX2interfaceshavebeenadded� • PerformanHOtoandfromthenewneighbor� • Logallappropriateparametersandconditionsincludingfulltracesofthecontrolanduserplanes fromthenetworkandUEsides� Evaluation o requency reuse: one deployment scenario

Basic test overview  • LocateaUEatthecelledge(in100percentothercellload)andpreparefull-buerdownloads� − Withoutothercellload,measureaveragethroughputfor30secondsforbothTCPandUDP� − With50percentothercellload,measuretheaveragethroughputfor30secondsforbothTCP andUDP� − With70percentothercellload,measuretheaveragethroughputfor30secondsforbothTCP andUDP� − With100percentothercellload,measuretheaveragethroughputfor30secondsforbothTCP andUDP� • Logallappropriateparametersandconditionsincludingfulltracesofthecontrolanduserplanes fromthenetworkandUEsides� • Comparethecell-edgeperformanceunderthevariousloadingconditionsandcomparethe measuredSINRforeachloadingconditionatthesamephysicallocation�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Basic QoS: user dierentiation between non-GBR users with dierent QCI

Basic test overview  • OneUE(A)shouldhaveafull-buerdownloadofUDPtracingoodradioconditionsandwith theQCIoflowestpriority� • OneUE(B)shouldhaveadownloadofaUDPstreamof10Mbpsandbelocatedinmediumradio conditionswithaQCIofsecond-lowestpriority� • OneUE(C)shouldhaveadownloadofaUDPstreamof10Mbpsandbelocatedinmediumradio conditionswithaQCIofhighestpriority� • Measuretheresultingthroughputandpacketloss(onUEBandC)andreporttheactualreceived throughputandtheS1andSGithroughput� • Othercellloadshouldbe70percentinULandDL� • Logallappropriateparametersandconditionsincludingfulltracesofcontrolanduserplanefrom thenetworkandUEsides� Note:Toensurethatcongestionoccurs,itmaybenecessarytonormalizethethroughputofUEBandC� Basic QoS: user-dierentiation between GBR and non-GBR users

Basic test overview  User

UE1

UE2

UE3

UE4

GBR DL (Mbps)

X1

X2

X3

X4

GBR UL (Mbps)

Y1

Y2

Y3

Y4

MBR DL (Mbps)

A1

A2

A3

A4

MBR UL (Mbps)

B1

B2

B3

B4

ARP (Allocation and Retention Priority is NOT equal for all ows)

N1

N2

N3

N4

Assume:N1>N2>N3>N4(User1hasthehighestpriorityandUser4hastheleastpriority)

• LocatefourUEingoodradioconditions�CongureDLbearerswithGBRvaluesforUE1,UE2, UE3,andUE4�EnsurethatX1,X2,X3,andX4DLthroughputsareaggregatedabovethecell capacityatallUElocationsbutthatX1,X2,andX3aggregatedarebelowthecellcapacity� • GenerateUDPDLtractoclientsUE1,UE2,UE3,andUE4� • StopDLtransferaeratleast30secondsofdatatransfertotheUEclients� • MeasureDLthroughput� • VerifythattheDLratesforUE1,UE2,andUE3arenolessthantheirpredenedGBRvalues(X1, X2,andX3,respectively)� • VerifythatUE4(lowest-prioritytrac)wasthemostnegativelyaected(theDLbitratefailedto achieveX4,whichisthedesiredDL-GBRforUE4)� • ChangetheARPsettingofUE4tobethehighestpriority(N1)� • RepeatwithsimultaneousDLtransfertoallfourUEclients� • VerifythattheDLdataratetoUE3(lowestpriorityamongallUEs)ismostnegativelyaected(its dataratewillbelowerthanitsdesiredDL-GBR)�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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• PerformthesametestbutlimittheS1downlinkperformancetocausecongestionatalevelbelow theRFcellcapacitybutabovetheaggregatedX1,X2,andX3�VerifythroughputisbelowtheS1 peakthroughputlimitation� − elimitationcanbeachievedviaVLANtuning� Basic application perormance: web browsing, streaming, voice calls, e-mail, VPN, on-line gaming

Basic test overview  • Identifytherelevantservicesforeachlocalenvironment� − Selectaheavilytrackedlocalwebsite: º 1-5MBforthemainpage(includingimages) − SelectaVoIPapplicationsupportedbytheoperatorandthelocalenvironment(forexample, Skype,GoogleChat,MSN,etc�)� − SelectalocalcorporatecustomerusingaVPNinamobileenvironment;theVPNconnection shouldhaveadatarateontheorderof2-10Mbpsend-to-end� − Identifythreelocal,well-recognizedservi ces: º Ahigh-requirement(low-latency)onlinegame º Ahighperformancexed-lineInternetservice(forexample,xDSL,packetcable,etc�) º Astreamingvideo(RTP/UDP)service • Executeandcomparetheapplicationperformanceonthefollowingaccesstechnologies: − HSPA(bestlocalcommercialavailableservice) − Fixed-lineInternetservice − LTEingood,medium,andpoorradioconditions • Logallappropriateparametersandconditionsincludingfulltracesofthecontrolanduserplanes fromthenetworkandUEsidesforLTEand,ifpossible,forHSPAandthexed-lineInternet service� − Forthevoiceservice,measureandcompareMOS� − Forthestreamingvideoservice,measureandcomparevideoMOSorasubjectivequality comparisonwithfriendlyusers� − Fortheonlinegame,getasubjectivestatementfromanexperiencedgamerandanE2Elatency measurement� • Reporttheabsoluteandrelativeperformancebetweenthedierentaccesstechnologies�

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Reerences EPS speciication reerences 3GPP TS

Title

24.301

Non-Access-Stratum (NAS) Protocol for Evolved Packet System (EPS); Stage 3 EPS NAS

S1-C

36.413

E-UTRAN: S1 Application Protocol (S1AP)

S1-C

36.423

E-UTRAN: X2 Application Protocol (X2AP)

X2-AP

X2-C

29.118

SGsAP

SGs

29.168

Mobility Management Entity (MME) -Visitor Location Register (VLR) SGs Interface Specs. Cell Broadcast Center Interfaces with the Evolved Packet Core; Stage 3

SBc-AP

SBc

29.272

MME Related Interfaces Based on Diameter Protocol

Diameter+

29.274

Evolved General Packet Radio Ser vi ce (GPRS) GTPv2-C Tunneling Protocol for Control plane (GTPv2-C); Proxy Mobile IPv6 (PMIPv6) based Mobility and Tunneling Protocols; Stage 3 PMIPv6

S3-C, S4-C, S5/8-C, S10, S11-C

S101

29.280

Optimized Handover Procedures and Protocols between EUTRAN Access and S101-AP cdma2000 HRPD Optimized Handover Procedures and Protocols between EUTRAN Access and S102-AP 1xRTT Access 3GPP EPS Sv Interface (MME to MSC) for SRVCC Sv

29.281

GPRS Tunneling Protocol User Plane (GTPv1-U)

S1-U, X2-U, S4-U, S5/8-U, S12-U

29.275 29.276 29.277

Protocol S1-AP

GTPv1-U

Interace(s)

S6a, S6d, S13

S5, S8 (PMIP)

S102 Sv

3GPP reerences

3GPP TS 23�272:CircuitSwitchedFallbackinEvolvedPacketSystem;Stage2 3GPP TS 24�301:Non-Access-Stratum(NAS)protocolforEvolvedPacketSystem(EPS);Stage3 3GPP TS 29�118:MobilityManagementEntity(MME)–VisitorLocationRegister(VLR)SGs interfacespecification TS 23�401:GeneralPacketRadioService(GPRS)enhancementsforEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN)access 3GPP TS 21�905:Vocabularyfor3GPPspecifications 3GPP TS 22�278:ServicerequirementsfortheEvolvedPacketSystem(EPS) 3GPP TS 43�318:GenericAccessNetwork(GAN);Stage2 TS 23�401:GeneralPacketRadioService(GPRS)enhancementsforEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN)access TS 24�301:Non-Access-Stratum(NAS)protocolforEvolvedPacketSystem(EPS);Stage3 TS 29�272:EvolvedPacketSystem;MMEandSGSNrelatedinterfacesbasedonDiameterprotocol TS 33�102:3GSecurity;Securityarchitecture TS 33�203:AccesssecurityforIP-basedservices TS 33�210:3GSecurity;NetworkDomainSecurity;IPnetworklayersecurity 

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

TS 33�401:3GPPSystemArchitectureEvolution(SAE):SecurityArchitecture; TS 36�300:EvolvedUniversalTerrestrialRadioAccess(E-UTRA)andEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN);Overalldescription;Stage2 TS 23�401:GeneralPacketRadioService(GPRS)enhancementsforEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN)access TS 24�301:Non-Access-Stratum(NAS)protocolforEvolvedPacketSystem(EPS);Stage3 TS 29�272:EvolvedPacketSystem;MMEandSGSNrelatedinterfacesbasedonDiameterprotocol TS 33�102:3GSecurity;Securityarchitecture TS 33�203:AccesssecurityforIP-basedservices TS 33�210:3GSecurity;NetworkDomainSecurity;IPnetworklayersecurity  TS 33�401:3GPPSystemArchitectureEvolution(SAE):SecurityArchitecture; TS 36�300:EvolvedUniversalTerrestrialRadioAccess(E-UTRA)andEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN);Overalldescription;Stage2 TS 36�420:X2layer1generalaspectsandprinciples TS 36�421:X2layer1 TS 36�422:X2signallingtransport TS 36�423:X2ApplicationProtocol(X2AP) TS 36�424:S2datatransport TS 29�281:GPRSTunnelingprotocolforuserplane(GTPv1-U) TS 23�401:GeneralPacketRadioService(GPRS)enhancementsforEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN)access TS 36�300:EvolvedUniversalTerrestrialRadioAccess(E-UTRA)andEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN);Overalldescription;Stage2 TS 29�305:InterworkingFunction(IWF)betweenMAP-basedandDiameter-basedinterfaces TS 29�274:TunnelingprotocolforControlplane(GTPv2-C);Stage3 TS 23�060:GeneralPacketRadioService(GPRS);servicedescription;Stage2 TS 36�410:S1layer1generalaspectsandprinciples TS 36�412:S1signallingtransport TS 36�413:S1Applicationprotocol(S1AP) TS 36�414:S1datatransport TS 29�281:GPRSTunnelingprotocolforuserplane(GTPv1-U)

27

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

28

TS 24�301:Non-Access-Stratum(NAS)protocolforEvolvedPacketSystem(EPS);Stage3 3GPP TR 22�968:StudyforrequirementsforaPublicWarningSystem(PWS) 3GPP TS 22�168:EarthquakeandTsunamiWarningSystem(ETWS)requirements;Stage1 3GPP TR 23�828:EarthquakeandTsunamiWarningSystem(ETWS),requirementsandsolutions TS 23�060:GeneralPacketRadioService(GPRS);servicedescription;Stage2 TS 23�107:QualityofService(QoS)conceptandarchitecture TS 23�203:PolicyandChargingControlArchitecture TS 23�401:GeneralPacketRadioService(GPRS)enhancementsforEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN)access TS 36�300:EvolvedUniversalTerrestrialRadioAccess(E-UTRA)andEvolvedUniversalTerrestrial RadioAccessNetwork(E-UTRAN);Overalldescription;Stage2 TS 23�002:Networkarchitecture TS 23�003:Numbering,addressingandidentification NGMN reerence

www�ngmn�org/uploads/media/White_Paper_NGMN_Beyond_HSPA_and_EVDO�pdf  ETSI reerence

ETSI TS 102 250-1:Speech Processing, Transmission and Quality Aspects (STQ); QoS aspects for popular  services in GSM and 3G networks: Part 1: Identification of Quality of Service aspects

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

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Glossary AAA

authentication, authorization, and accounting

AMR

adaptive multi-rate

AMR-WB

adaptive multi-rate wideband

APN

access point name

ASP

application service provider

BICC

bearer-independent call control

BLER

block error rate

BSC

base station controller

BTS

base transceiver station

CAPEX

capital expenditures

CDF

cumulative distribution function

CDMA

code division multiple access

CLID

calling line identication

CLIP

calling line identication presentation

CSUDI

circuit-switchedunrestricteddigitalinformation

CSFB

circuit-switched fallback  

DL

downlink  

DMT

data mining toolkit

E2E

end-to-end

eNodeB

evolvedNodeB;NodeBisaUMTSbasetransceiverstation(BTS)

EPC

evolved packet core

EPS

evolved packet system

ESN

electronic serial number

ETSI

European Telecommunications Standards Institute

eUTRAN

evolvedUMTSterrestrialradioaccessnetwork;alsoabbreviatedasE-UTRANorEUTRAN

FSS

frequency-selective scheduling

GGSN

gateway GPRS support node

GPRS

general packet radio service

GUI

graphical user interface

HA

home agent

HARQ

hybrid automatic repeat request

HLR

home location register

HO

handover

HTTP

hypertext transfer protocol

IM

instant messaging

IMS

instant messaging service

IMSI

international mobile subscriber identity  

Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

IP-TV

Internet protocol television

IOT

inter-oce trunk  

IP

Internet protocol

IRAT

inter-radio access technology  

KPI

key performance indicator

LCS

location services

LSTI

LTE SAE trial initiative

LTE

Long term evolution

MGW

media gateway  

MIMO

multiple-input/multiple-output

MSC

mobile switching center

MSC-S

mobile switching center server

MSS

mobile soswitch

MSTV

Maximum Service Television

NAI

network address indicator

NE

network element

NEM

network equipment manufacturer

NGMN

next-generation mobile networks

OCNG

OFDMA channel-noise generation

OFDM

orthogonal frequency-division multiplexing

OPEX

operating expenses

OLAP

online analytical processing

PCF

packet control function

PDSN-FA

packetdataservingnode,foreignagent

PDSN-HA

packetdataservingnode,homeagent

PoC

proof of concept

PSTN

public switched telephone network  

QCI

QoS class identier

QoE

quality of experience

QoS

quality of service

QoSM

Quality of Service Manager

RNC

radio network controller

ROHC

robust header compression

RRC

radio resource control

SAE

System Architecture Evolution

SC-FDMA

single-carrierfrequency-divisionmultipleaccess

SCTP

Standard Control Transmission Protocol

SFN

single-frequency network  

SGSN

serving GPRS support node

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Application Note: LTE and EPC Test—An Overview of Test Concepts and Tools for Trials

SIP

session initiation protocol

SMS

short messaging service

SON

self-optimizing network  

STP

signaling transfer point

TDR

transaction detail record

TTI

transmission time interval

UE

user equipment

UMTS

Universal Mobile TelecommunicationsSystem

UL

uplink  

URI

uniform resource indicator

USSD

unstructured supplementary ser vice data

VIP

very important person

VoIMS

voice over instant messaging ser vice

VoLGA

voice over LTE generic access

WAP

Wireless Application Protocol

WSP

wireless service provider

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