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JOINTWHITEPAPER
Empowering5GDataPathfor
TimeSensitiveNetworking
(時間敏感網絡技術賦能5G確定性數(shù)據傳輸)
June2023
Empowering5GDataPathforTimeSensitiveNetworking
WhitePaper
Foreword
Thedeterministicnetworkisthecoretechnologytosupportdigitaltransformation,
anditisalsooneofthemostimportantroadmapsforthefuturewireless
communicationnetworks.5Gtechnology,asthemostcutting-edgecommunication
technology,shouldbeintegratedwiththeTime-SensitiveNetworking(TSN)
technologytobedeterministic.Withthecontinuousadvancementofdeterministic
characteristicsinthe5Gstandardsandspecifications,aswellasthecontinuous
popularizationof5Gnetworkcoverageandverticalindustryapplications,the
integrationof5GtechnologyandTSNtechnologyhasbecomeparticularlyimportant.
AppliedScienceandTechnologyResearchInstitute(ASTRI)andPengCheng
Laboratory(PCL)aretwoofthelargestR&DcentersintheGreaterBayArea(GBA),
withthestrongestR&Dbackgroundinnetworkingandcommunicationstechnologies.
Inthiswhitepaper,ASTRIandPCLhavejointlydevelopedandshowcasedtheend-
to-end5GdataplaneintegratingwithTSNtechnologyandhaveachievedhigh-
precisiontimesynchronizationwithminimizedjitter.Theresearchresultsare
positiveandinstructivetoexplore5Gverticalapplicationscenarios,leading
industrialevolutioninsmartmanufacturing,power,andminingindustries.
JustinChuang,PhD.
CommunicationsTechnologies,VicePresident,ASTRI
Author:
PCL:JimanLv,JingbinFeng,JianCheng,ChunlaiCui,HuaWang,RongjunXu,Sen
Ma,ShuangpingZhan,WeibinYe
ASTRI:YolandaTsang,LiangDong,JianjunZhang,AndyHuang,SteveLi,WilliamXia,
LawrenceLuo
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TableofContents
Foreword........................................................................................2
ListofFigures..................................................................................5
ListofTables...................................................................................6
1.Introduction.................................................................................7
1.1Background&MarketNeeds........................................................7
1.25GandTSN:IT/OTConvergence...................................................7
1.2.15GRoadmapin3GPP..............................................................7
1.2.2IEEE-StandardizedTSN............................................................9
1.2.3TSN-enabled5GSystem........................................................10
1.3Collaborations.......................................................................11
1.3.1PengChengLaboratory.........................................................11
1.3.2HongKongAppliedScienceandTechnologyResearchInstitute..........12
1.3.3WhitePaperHighlight..........................................................12
2.KeyChallenges............................................................................13
2.1RequirementsofVerticalIndustries.............................................13
2.2End-to-EndTimeSynchronizationChallenges..................................14
2.3End-to-EndLowLatencyandDeterminism......................................16
2.4QoSMappingforTSNFlows........................................................17
3.3GPPSpecificationforTSN-enabled5Gsystem......................................20
3.1PacketDataUnitSession..........................................................20
3.25GSActingasaBridgeinTSN.....................................................21
3.3TimeSynchronization..............................................................21
3.3.15GSTimeSynchronization.....................................................22
3.3.2End-to-EndTimeSynchronization.............................................22
3.4EnhancementsforQoSMappings.................................................22
4.DataServiceSolution....................................................................25
4.1ArchitectureofEnd-to-EndSynchronizationSolution.........................25
4.1.1TimestampModelling...........................................................25
4.1.2Solutionof5GSTime-DomainSynchronization..............................26
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Empowering5GDataPathforTimeSensitiveNetworking
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4.1.3TSN-enabled5GEnd-to-EndSynchronizationSolution.....................27
4.2End-to-endDeterministicSchedulingScheme..................................29
4.2.15GandTSNQoSMapping.......................................................29
4.2.2End-to-EndDeterministicTrafficScheduling................................30
4.2.3Supportingholdandforwardbufferingmechanism(DS-TT/NW-TT).....31
5.Evaluation.................................................................................32
5.1SolutionArchitectureofTSN-enabled5GCoreProofofConcept(PoC)....32
5.2CollaborationResultsfromActualDeploymentEvaluationSetup...........33
5.3Evaluation,Discussion&Results.................................................35
5.3.1End-to-endtimesynchronizationtest........................................35
5.3.2Jitterinend-to-endpacketforwarding......................................38
5.3.3Failovertesting.................................................................39
5.3.4Simulatedindustrialuse-case.................................................41
5.3.5Testresultevaluations.........................................................42
6.Summary/Conclusion.....................................................................43
6.1IndustrialInternetusecases......................................................43
6.2What’snext..........................................................................45
ListofAcronymsandAbbreviations.......................................................47
References....................................................................................50
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ListofFigures
Figure15GSystemasatime-awaresystem[Source:TS23.501Figure5.27.1-1]..10
Figure25GSasaTSNbridge[Source:TS23.501Figure5.28.1-1]....................11
Figure3QoSdifferentiationwithinaPDUSession[source:]..20
Figure4QoSMappinginTSNAFandPCFarchitecture[Source:TS23.501Figure
5.28.4-1]......................................................................................23
Figure5UserdatahandlingintheUPF[Source:TS23.501Figure-1]......24
Figure6End-to-EndSynchronizationSolution...........................................25
Figure7NW-TTTimingAlgorithm.........................................................26
Figure8TSN-enabled5GsystemEnd-to-Endsynchronizationdemosolution......27
Figure9gPTPrelayinstancemodel.......................................................28
Figure10TrafficScheduling...............................................................31
Figure11CompletePCLandASTRIsolutionarchitecturewith5GNetworkFunctions
.................................................................................................32
Figure12ActualArchitectureofTSN-enabled5GsystemDemoArchitectureSetup
.................................................................................................34
Figure135GSystemsynchronizationviadirectconnection..........................36
Figure145GSystemsynchronizationviaGPS...........................................37
Figure15FailovertestwithtwoCPEsand2gNB.......................................40
Figure16Simulatedindustrialusecase..................................................41
Figure17Release17architectureofTSC................................................46
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ListofTables
Table1ExamplesofIEEETSNTaskgroupstandards.....................................9
Table2ExamplesofindustrialautomationintypicalapplicationscenariosofTSN-
enabled5Gsystem[Source:5GACIAWhitePaper,“Integrationof5GwithTime-
SensitiveNetworkingforIndustrialCommunications”]................................14
Table3Clocksynchronizationserviceperformancerequirementsfor5GSystem
[Source:TS22.104v17.7.0Table5.6.2-1]................................................15
Table4Standardized5QItoQoScharacteristicsmapping[Source:TS23.501Table
5.7.4-1]........................................................................................19
Table6Jitterof5GSystemsynchronizationviadirectconnection,withbackground
flow(512bytes,100Mbps)..................................................................38
Table7Jitterof5GSystemsynchronizationviaGPS,withbackgroundflow(512bytes,
100Mbps)......................................................................................39
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1.Introduction
1.1Background&MarketNeeds
In“IndustrialInternetInnovationandDevelopmentPlan(2021-2023)”,ithasclearly
mentionedthetechnology“TimeSensitiveNetwork(TSN)overtheFifthGeneration
(5G)telecommunicationtechnology”beingoneofthekeyinnovativetechnologies.
Previously,theTSNhasbeenawirelinetechnologycommonlyusedinfactoriesfor
deterministicservices.However,beingawirelinetechnology,thewirehaslimited
theusagescopeaswellasitsapplicationbecauseofdifferentconsiderations,such
asspaceandconnectionsneededbetweendifferentdevices.IndustrialInternet,also
knownasthefourthindustrialevolution(Industry4.0),iswellagreedtobethe
cornerstonefortherevolutionoftheindustry.MobilizedTSNbecomesawaytogo
and5Ghasbeenselectedasthemobiletechnologywhichwillbemergingwiththe
TSNtointerconnectpeople,machines,things,systems,etc.,toformanewecology.
TSN-enabled5Gsystemdoesnotonlydigitalizepeople’sliving,butalsocreatesa
newerafortheconnectedanddigitalizedindustrialindustry.
InarecentreportfromtheChinaAcademyofInformationandCommunication
Technology,ithasshownthat,fromonlythefirstquarterof2022,China’sIndustrial
Internetindustryhasmadeovertrillionyuan,anenticingresultfromthedigital
transformationoftheindustrialenterprises.Ontheotherhand,the5Gnetworkis
wellknownforitssupportofultra-lowlatencycommunicationsandlargebandwidth.
TheIndustrialInternetisexpectedtobethekillerapplicationfor5G.Ithasbeen
projectedthatthe5Gverticalapplicationspenetrationratewillreach35%in2023
formainlandChinaalone.Theintegrationof5GandtheIndustrialInternetis
acceleratingChina’snewindustrializationprocessandservingasabreedingground
forChina’seconomicdevelopment.
1.25GandTSN:IT/OTConvergence
1.2.15GRoadmapin3GPP
Thefifth-generationmobilecommunicationtechnology(referredtoas5Gor5G
technology)isthelatestgenerationofmobilecommunicationtechnology.Itisa
telecommunicationandinformationtechnology(IT)definedbythe3rdgeneration
partnershipproject(3GPP),evolvingfromthe4G,3G,and2Gsystems.In5GNew
Radio,or5GNR,theenhancementsofthemulti-antennaenhancementtechnologies
improvethespectrumdiversityandefficiency,modulationandcodingtechniques
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Empowering5GDataPathforTimeSensitiveNetworking
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forbettercellcoverage,andslottimeoperationsforsystemflexibility.Asaresult,
5Gprovidesahigherdatatransmissionrateandyetultra-lowlatencyservicesas
comparingto4G.
Therearethreemajordeploymentscenariosfor5Gnetworks:
-EnhancedMobileBroadband(eMBB):largebandwidthandmoderate
latencyforusecases,suchasemergingAR/VRmediaandapplications,low
bandwidthtransmissionsformachine-to-machinecommunication.
-MassiveMachineTypeCommunications(mMTC):lowcost,lowpowerwide
areaforlatency-sensitiveapplications,suchastheInternetofThings(IoT)
thatconnectallphysicalthings(peopletopeople,peopletothings,things
tothings,etc.)
-Ultra-ReliableLowLatencyCommunications(URLLC):extremelylow
latencyapplications,suchasforvehicle-to-vehicleandvehicle-to-
infrastructurecommunications.
3GPPRelease15marksthebeginningofthe5Gera,thearchitecturehas
revolutionarychangefromthepreviousgeneration.The3majorchangesinthe
architectureincludetheControlandUserPlaneSeparation(CUPS),Service-based
Architecture(SBA)infrastructure,andnetworkslicing.InCUPS,theseparationof
controlanduserplanedelocalizestheneedofplacingallthenetworkentitiesnearby
inthenetwork,allowingamoreflexibleandexpandibledeployment.Forinstance,
placingtheuserplaneentityclosertothebasestationallowsedgecomputingwith
lowerlatencyforapplication.TheSBAinfrastructurehasmodulatedthenetwork
coreintonetworkfunctions(NFs),wheretheNFsareinterconnectedbyHTTP2
protocols.Theservice-basedinterfacehassimplifiedtheprotocolsbetween
differentNFs,allowingthedeployment,upgrades,andscalingtobemoreefficient,
whichinturnrealizingfastertime-to-marketfornewfunctionsandfeatures.The
networkslicingaimstocreateseparationofthenetworkintoslicesfordifferent
marketsandneeds.Witheachslicebeingisolatedfromtheotherslices,the
resourcescanbesharedbutresourceineachslicemeetingdifferentrequirements.
EvolvingfromRelease15,the3GPPstandardscontinuetoevolvetoconnectvirtually
everythingandeveryonetogether,deliveringhigherdatarateswithlowerlatency,
becomingmorereliablehaveofferingabetterexperience.Withtheseperformance
enhancementsandefficiencyimprovements,newuserexperiencesandnew
industriesarebeingenabled.Release15isknowntobethe5GPhase1,Release16
being5GPhase2andRelease17beingthe5Genhancements.Release15laysthe
foundationofthenewarchitectureandsecurity,andRelease16addsmorefeatures
foradditionalusecases,forexampleenablingtheapplicationsfornewverticalsof
deploymentscenariowhichincludestheNon-PublicNetworks(NPN),positioning
services,NRCellularIoT,URLLC,andTSN.Release17protocolfreezewasinJune
2022,supportingnewusecasesandverticalssuchascoverageandpositioning
enhancements,enhancedsupportofNPNs,supportingunmannedaerialsystems,
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supportforedgecomputingin5GCore(5GC)andnetworkautomationfor5G(Phase
2).Release18hasbeennamed5GAdvancedasitintroducesintelligence(machine
learningtechniques)intothewirelessnetworksatdifferentlevelsofthenetwork.
1.2.2IEEE-StandardizedTSN
IEEETimeSensitiveNetworkingTaskGroupispartoftheIEEE802.1workinggroup.
ItisanOperationTechnology(OT)toprovidedeterministicservicesthroughIEEE
802networks,intimesynchronization,boundedlatency,reliability,andresource
management.SomeofthestandardsintheIEEE802.1arelistedinTable1.
Table1ExamplesofIEEETSNTaskgroupstandards
IEEEDescriptionInformation
Standards
IEEE802.1ASTimingandProtocolandproceduresusedtoensurethatthe
Synchronizationsynchronizationrequirementsaremetfortime
sensitiveapplications.
IEEEEnhancementsforTime-awarequeue-drainingprocedures,managed
802.1QbvScheduledTrafficobjectsandextensionstoexistingprotocolsthat
enablebridgesandendstationstoschedulethe
transmissionofframesbasedontimingderivedfrom
IEEE802.1AS.
IEEEFramePre-emptionProvidereducedlatencytransmissionforscheduled
802.1Qbutime-criticalframesinabridgedlocalareanetwork.
IEEE802.1CBFrameReplicationandProcedures,managedobjectsandprotocolsfor
Eliminationforbridgesandendstationstocreateandeliminate
Reliabilityduplicateframes.
OneofthemostimportantTSNtaskgroupstandardsisIEEE802.1AS(time
synchronization)whichisbasedontheIEEE1588protocol.TheIEEE802.1ASprecise
clocksynchronizationprotocoliscommonlyknownasthegeneralizedPrecisionTime
Protocol(gPTP)generalizedclocksynchronizationprotocoltodistributetimeacross
thenetworkdomain.Theportinthistime-awaresystemutilizesamasterslave
paradigminwhichthemastersendsthetimesynchronizationinformationtothe
slaveportofatime-awaresystem,whiletheslavereceivesthatinformationfrom
themasterport.Theonewithallitsportsinthemasterstateisknownasthe
Grandmaster(GM)anditisthetimesourceofthenetwork.Inanetwork
environmentwithamaximumof7hops,gPTPcantheoreticallyensurethattheclock
synchronizationerrorisinunitsofnanoseconds.
Boundedlatencyordeterministicend-to-endlatencyisdefinedinIEEE802.1Qbvfor
trafficschedulingandmanagementoftime.Itdefinesthequeuingmanagement,
gating,andtrafficshapingtoensurethetime-criticalflowsarescheduledbasedon
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Empowering5GDataPathforTimeSensitiveNetworking
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servicelevel,thusavoidingmutualinterferencebetweentrafficofdifferent
priorities.
1.2.3TSN-enabled5GSystem
Startingfrom3GPPRelease16,the5Gsystem’srolehasbecominglikeanindustry-
gradecommunicationfabric.InRelease16,ithasintroducedtheintegrationofthe
5Gsystem(5GS)withtheTime-SensitiveNetworkingtaskgroupoftheIEEE802.1
workinggroupinsupportoftheindustrialautomationvertical,convergingtheITand
OT.
IntheliaisonstatementS2-1908630fromthe3GPPSAWG2(SA2)totheIEEE802
workgroup,3GPPhasintegratedtransparentlyasthe5GSystemasalogicalTSN
bridgetosupporttime-sensitivecommunication.InRelease16,itwillsupport:
IEEE802.1Qcc:threeTSNconfigurationmodels
IEEE802.1QbvbasedQoSschedulingforinterworkingwithTSN
IEEE802.1QAnnexQ.2(“Usinggateoperationstocreateprotected
windows”)forsimplifiedtrafficscheduling
IEEE802.1ASfortheentireend-to-end5GSystemasa“time-awaresystem”
forTSNsynchronization.
InTSN-enabled5Gsystem,the5GSystemisactingasavirtualgPTPtime-aware
system(IEEE802.1AS)wherethe5GCisactingasaTSNbridgeportwithtime
synchronizationbetweentheTSNsystemclockandthe5Gclock.
The5GSisperceivedasanIEEE-compliantvirtualEthernetTSNbridge.Attheedges
ofthe5GS,Network-SideTSNTranslator(NW-TT)andDevice-SideTSNTranslator
(DS-TT)aresynchronizedwiththe5GGMclock(i.e.,the5Ginternalsystemclock)
tokeepthesenetworkelementssynchronized,seeFigure1forillustration.
:5GStimingdirection
(g)PTPtimingdirection
:5GStimesynchronization
5GTime5GS
Domain5GGM
5GS:(g)PTPtimesynchronization
TSeTSi
5GS5GS5GS
(g)PTP
NW-TTGM
EndUuTEPTP-
DS-TTUEgNBcompatibleTransp.t5GUPFBridge
StationtransportExternalEnd
networkStation
5Gsystemcanbeconsideredasan
802.1AStime-awaresystemorIEEE1588BoundaryorTransparentClock
Figure15GSystemasatime-awaresystem[Source:TS23.501Figure5.27.1-1]
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In3GPP,thedatasessionisknownasPacketDataUnit(PDU)Sessionbetweenthe
userequipment(UE)andthedatanetwork(DN)viatheUserPlaneFunction(UPF)
actingasaPDUSessionAnchor(PSA).Intheschematicdiagramofthe5Gbridge
system,each5GbridgeconsistsofportontheUE/DS-TTsides,userplanetunnels
(PDUsession)betweentheUEandUPF,andportsontheUPF/NW-TTside.Theport
ontheUE/DS-TTsideisboundtoaPDUsession,andtheportontheUPF/NW-TT
sidesupportsconnectionwiththeexternalTSNnetwork,asshowninFigure2.Inthe
5GS,fromNW-TTtoDS-TT,isconsideredasasinglebridgewhiletherecouldbe
morethanoneUPFsinvolvedintheend-to-endconnection.Eachbridgewillbe
assignedauniquebridgeidentifierforuseintheTSNdomain,e.g.,the
configurationsinCNCandTSNAF.
BridgeA
UPF-A
NW-TTTSN
System
TSNDS_TTUE1
Bridge/
EndDS-TT
Station
UPF-BNW-TT
TSN
Bridge/DS-TTUE2
End
Station
BridgeB
Figure25GSasaTSNbridge[Source:TS23.501Figure5.28.1-1]
1.3Collaborations
1.3.1PengChengLaboratory
PengChengLaboratory(PCL)isanadvancedandinnovativeresearchinstitution
inthefieldofnetworkcommunicationsandartificialintelligenceinChina.Itis
focusinginsolvingstrategic,forwardlooking,fundamentalyetcritical
scientificproblems.Itisamajorcontributortothisfield,supporting
nationalstrategicscienceandtechnologyefforts.
PCLisalaboratorywithateamoftalentedresearchersandengineerstodevelop
networkcommunicationprojectstofullyenablelarge-scaleindustrialusecases,
suchassmartmanufacturing,smartcity,IndustrialInternet,andartificial
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Empowering5GDataPathforTimeSensitiveNetworking
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intelligence(AI).OneoftheresearchfocusesofPCListofacilitatethedeterministic
transmissionrequirementsoftheIndustrialInternetandhigh-endequipment
scenarios.PCLhasbeenresearchinganddevelopingTSNchipsandplatform
equipmenttoachievethedeterministicnetworkservicecapabilitieswith
controllablebandwidthanddelay.Throughcollaborationofinnovativewiredand
wirelesscommunicationtechnologies,afullyconnected“5G+IndustrialInternet”
factorycouldbeachievedbyintegratingthekeytechnologiesof5GandTSN.
1.3.2HongKongAppliedScienceandTechnologyResearchInstitute
HongKongAppliedScienceandTechnologyResearchInstitute(ASTRI)wasfounded
bytheGovernmentoftheHongKongSpecialAdministrativeRegioninyear2000with
themissionofenhancingHongKong’scompetitivenessthroughappliedresearch.
TheCommunicationsTechnologies(CT)DivisionofASTRIdeliverscutting-edge5G
networktechnologiesandapplications,andothernext-generationnetworksolutions.
Itsapplicationsarehelpingmanufacturers,operators,andsolutionprovidersto
introducefasterandmoreintelligentservicesfornetworkusers,benefitingboth
industriesandthecommunity.
ASTRIissupportingHongKong’sdigitaltransformation,re-industrialization,and
Industry4.0upgradeintermsofstandards,solutions,andinfrastructure,especially
in5G-relatedtransformationswithTSNtechnologies.ASTRIisdevelopingopen
broadbandwirelessnetworksandapplications,including5Gbasestationsandcore
networks,andfocusingoncreatingnewtechnologyinfrastructureandplatformsfor
awiderangeofsectorsandapplications.ASTRIalsooffersend-to-endsystem
solutions(Easy5G)withTSN-enabledforvariousplayersatdifferentlevelsofthe
valuechainintheindustryecosystem.
1.3.3WhitePaperHighlight
ThevisionofthiswhitepaperistosupportthemainlandChinaGovernment'sAction
PlanforIndustrialInternetInnovationandDevelopmentandTheGuidelinesforthe
Constructionof5GFullyConnectedFactoriesandtosupporttheHongKong
Government'sre-industrializationplanwhichemphasizestherequirementsforTSN-
enabled5Ginfrastructuretosupportdigitaltransformationandre-industrialization
forsmartmanufacturing,power,andtransportationindustrieslocallyinChina
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