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JOINTWHITEPAPER

Empowering5GDataPathfor

TimeSensitiveNetworking

(時(shí)間敏感網(wǎng)絡(luò)技術(shù)賦能5G確定性數(shù)據(jù)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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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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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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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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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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