J- 面向6G时代前沿技术初探量子信息技术QITs-2024-20240403-v4.0-EN

ExecutiveSummary

In2023,ITU-RissuedtheIMT-2030frameworkhighlightingsustainability,security,andresilience,

connectingtheunconnected,andubiquitousintelligenceasoverarchingaspectswhichactasdesignprinciples

commonlyapplicabletoallusagescenarios.InanotherrecommendationaboutthefuturedevelopmentofIMTfor

2030andbeyond,ITU-RmentionsthatquantumtechnologywithrespecttotheRANisapotentialtechnologyto

ensuresecurity,andresiliencewhenallowingforalegitimateexchangeofsensitiveinformationthroughnetwork

entities.Therefore,thetargetisbecomingmoreclearertoapplyquantumtechnologyinachievingsecureand

resilienceinthe6thgeneration(6G)communicationandbeyond.Tothisend,inthisannuallyrevisedwhitepaper,

weintroduceresearchprogressinapplyingquantuminformationtechnologies(QITs)tocommunicationand

networkandcomputingoverthepastyearandproposesomeexpectationsofquantumtechnologyresearchin2024.

Chapter2focusesonquantumsecurecommunicationaimingatsafeguardingcriticalinformationbyapplying

quantummechanisms.Theintroductionstartswithvarioustheoriesandexperimentscontinuouslycarriedoutin

quantumkeydistribution(QKD),quantumrandomnumbergenerator(QRNG),andquantuminformationnetwork

(QIN),followedbystate-of-the-artstandardizationactivitiesforQKDallovertheworld.Intheimplicationsfor6G,

quantumencryptiondemonstrationdeployedontheinternetofvehicles;integratedcontinuousvariableQKD

(CV-QKD)withG.698.4device;anddeployingquantumcryptographyinthe6Gnetworkareintroduced

respectively.

Chapter3givesinsightintotheresearchofhowtosatisfythedramaticallyincreasedcommunicationsystem

performanceandrichdiversityofinnovativeservicesexpectedby6Gbyapplyingquantumcomputing.Firstly,

computingscenariosandkeyissuesforcommunicationareanalyzed,includingsignalprocessing,network

optimization,serviceprocessing,andnetworkintelligentization.Secondly,a"Classical+Quantum"hybrid

computingplatformwitharobustcomputationalfoundationisproposedtoprovidecomputationalsupportservices

tailoredtodifferentdomains,facilitatingresearchinnovationandproductimplementation.Thirdly,theimplications

ofquantumcomputingfor6Gareintroducedwiththreeexamples,whichapplyquantumcomputingtosolve

classicalcommunicationissues,respectively.

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Basedonthebarrier-breakingachievementsin2023,2024willprobablymarkasignificantyearforquantum

computingtechnology,fromwhenthefieldofquantumcomputingisexpectedtotransitionfromphysicalqubitsto

error-correctinglogicquantumbits,andanti-quantumcryptographyresearchisexpectedtospeedupaswell.

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TableofContents

ExecutiveSummary........................................................................................................................................................1

1.Introduction...............................................................................................................................................................4

2.QuantumCommunicationandNetwork..............................................................................................................6

2.1.KeyTechnologies........................................................................................................................................6

2.1.1.QuantumKeyDistribution...................................................................................................................6

2.1.2.QuantumRandomNumberGenerator.................................................................................................8

2.1.3.QuantumInformationNetwork............................................................................................................9

2.2.StandardizationActivitiesforQKD..........................................................................................................10

2.2.1.ChineseStandardizationProgress......................................................................................................10

2.2.2.InternationalStandardizationProgress..............................................................................................12

2.3.Implicationsfor6G.....................................................................................................................................16

2.3.1.QuantumEncryptionintheInternetofVehicles...............................................................................16

2.3.2.QuantumEncryptionIntegrationwithBearerNetworkEquipment..................................................17

2.3.3.QuantumCommunicationSecurity....................................................................................................18

3.QuantumComputing.............................................................................................................................................20

3.1.ComputingScenariosandKeyIssuesforCommunication................................................................20

3.1.1.SignalProcessing...............................................................................................................................20

3.1.2.NetworkOptimization........................................................................................................................21

3.1.3.ServiceProcessing..............................................................................................................................22

3.1.4.NetworkIntelligentization.................................................................................................................22

3.2.QuantumHybridHeterogeneousComputing................................................................................................23

3.3.Implicationsfor6G........................................................................................................................................26

3.3.1.Single-CellMassiveMIMOAntennaOptimization...........................................................................26

3.3.2.MIMOBeamSelectionofMultipleCellular......................................................................................28

3.3.3.PhaseCorrectionofMillimeterWaveSignals...................................................................................31

4.FutureExpectation.....................................................................................................................................................34

5.Acknowledgement.....................................................................................................................................................35

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1.Introduction

Thescopeofthisannuallyrevisedwhitepaperistointroducethelatestresearchprogressaboutquantum

informationtechnologies(QITs)fulfillingstringentdemandsofcommunicationandcomputingenvisagedin6Gor

beyond6G.InadditiontobenefitsexpectedfromQITstocommunicationandnetworkandcomputing,thisversion

of2024whitepaperproposessomeexpectationsofquantumtechnologyresearchin2024.

Chapter2.QuantumCommunicationandNetwork

Chapter2focusesonquantumsecurecommunicationaimingatsafeguardingcriticalinformationbyapplying

quantummechanisms.

In2023,varioustheoriesandexperimentshavecontinuouslybeencarriedoutinthefollowingkeytechnologies.

Forquantumkeydistribution(QKD),progresshasbeenmadeinnewprotocolsandclassicalquantum

co-transmissionstudies,etc.,andtheperformanceofQKDsystemshasbeenfurtherimproved.Quantumrandom

numbergenerator(QRNG)technologyiscurrentlybeingdevelopedandimprovedtoachievemoreefficientand

stableQRNGs.Manylaboratoriesandresearchinstituteshaveconductedanumberofexperimentstoverifythe

feasibilityandstabilityofquantumInformationNetwork(QIN).

AboutthestandardizationactivitiesforQKD,majorstandardizationorganizationshaveactivelycarriedoutthe

preparationofQKDrelatedstandards,coveringterminologydefinitions,applicationscenariosandrequirements,

networkarchitecture,equipmenttechnicalrequirements,QKDsecurity,testingandevaluationmethods,andother

aspects.

Inthelast,theimplicationsofquantumtechnologiesfor6Garediscussedfromthefollowingthreeaspects:

quantumencryptiondemonstrationdeployedontheinternetofvehicles;integratedcontinuousvariableQKD

(CV-QKD)withG.698.4devicetoconvergeQKDintoclassicalcommunicationnetworkandthusmakefulluseof

existingtelecominfrastructure;anddeployingquantumcryptographyinthe6Gnetworktoachievetheoverall

securitymanagementofthecommunicationsystemareintroduced.

Chapter3.QuantumComputing

Tosatisfythedramaticallyincreasedcommunicationsystemperformanceandrichdiversityofinnovativeservices

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expectedby6G,Chapter3givesinsightintotheresearchofhowtoenhancecommunicationbyapplyingquantum

computing.

Firstly,consideringthattheessenceofcommunicationisaseriesofmathematicalcalculations,ahierarchical

communicationnetworkfromacomputingperspectiveisdescribedtofacilitatetheanalysisofcomputingscenarios

andkeyissuesforcommunicationincludingsignalprocessing,networkoptimization,serviceprocessing,and

networkintelligentization.

Secondly,a"Classical+Quantum"hybridcomputingplatformwitharobustcomputationalfoundationisproposed

toprovidecomputationalsupportservicestailoredtodifferentdomains,facilitatingresearchinnovationandproduct

implementation.Especially,thearchitecturedesignofthishybridcomputingplatformconsidersprinciplesand

conceptsofmodularity,standardization,widecompatibility,autonomoussecurity,andintelligenceefficiency.

Thirdly,theimplicationsofquantumcomputingfor6Gareintroducedwiththreeexamples,whichapplyquantum

computingtosolveclassicalcommunicationissues,respectively.Thethreeexamplesinclude:solvingsingle-cell

massiveMIMOantennaoptimizationbyusingtheFilteringVariationalQuantumAlgorithm(FVQE),solving

MIMObeamselection(MBS)bydesignedquantumalgorithmsbasedonCoherentIsingmachines(CIM),solving

phasecorrectionofmillimeterwavesignalsbyapplyingaphaseoffsetcorrectionmodelobtainedwithQuantum

SupportVectorMachine(QSVM)algorithmontheterminalsideandthusreducingreferencesignalingoverheads.

Chapter4.FutureExpectation

Inthelastquarterof2023,wewitnessedanindustrymilestoneinthequantumarea,i.e.,breakingthe1,000-qubit

barrier,givingquantumcomputersmorecomputingpowerthaneverbefore.Meanwhile,specialistsfromacademia

createdaquantumcomputerwiththelargest-evernumberoflogicalquantumbitsi.e.,48logicalqubits,wherein

thelogicalqubitsratherthanthehardware-basedqubitsarepromisingtoreducethemassiveamountsof

error-correctingsufferedbyquantumcomputers.Consequently,2024willprobablymarkasignificantyearfor

quantumcomputingtechnology,fromwhenthefieldofquantumcomputingisexpectedtotransitionfromphysical

qubitstoerror-correctinglogicquantumbits,andanti-quantumcryptographyresearchisexpectedtospeedupas

well.

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2.QuantumCommunicationandNetwork

2.1.KeyTechnologies

2.1.1.QuantumKeyDistribution

Quantumcommunicationisbasedonquantumsuperpositionorentanglementtorealizekeydistributionor

informationtransmission,whichisunconditionallysecureatthetheoreticallevel.Quantumkeydistribution

(QKD)isthemostdevelopedquantumcommunicationtechnologybasedonthebasicprinciplesofquantum

mechanics,combinedwiththeencryptionmethodof"oneencryptionatatime"totransferthekeybetween

communicationusers.

In2023,variousQKDtheoriesandexperimentshavecontinuouslybeencarriedout,progresshasbeenmadeinnew

protocolsandclassicalquantumco-transmissionstudies,etc.,andtheperformanceofQKDsystemshasbeen

furtherimproved.AjointteamledbyTsinghuaUniversitygaveasecurityproofofthedevice-independentQKD

(DI-QKD)protocolbylinkingcomplementaritytoquantumnonlocalityandprovidedanewtheoreticaltoolforthe

practicalimplementationofDI-QKD1.AjointteamledbytheAustralianNationalUniversity(ANU)proposeda

measurementDI-QKDprotocolthatrequiresthepreparationofhigh-dimensionalquantumstatestobemeasured

usingthecoherenttotalphotonnumbermethod,andsimulationsshownthatitcanbreakthePLOBlimitatshorter

distancesthanTwin-Fieldprotocolswhenencodedina7-dimensionalstate2.Acollaborativeeffortspearheadedby

theChinaAcademyofTelecommunicationsResearch(CATR)hassuccessfullydemonstratedaremarkabletotal

transmissiondatacapacityof1Tbpswithinanopticaltransportnetwork.Thisachievementwasrealizedover

100.96kmthroughco-fibertransmissionemployingfew-modefiber,generatingaquantumsecuritykeyrate(SKR)

of2.7kbps3.QKDexperimentsusingsolid-statesingle-photonemittersareattractingincreasingattentiondueto

theirrapidlyimprovingperformanceandcompatibilitywithfuturequantumnetworks.Thejointteamledby

Heriot-WattUniversity(UK)conductedQKDexperimentsusingInGaAsquantumdotsasasingle-photonsource,

generatingafinitekeyof13kbpsat100km,inone-minuteacquisitiontime4.Theseresearchresultsarehelpfulin

exploringQKDapplicationsandrealizinglarge-scaleQKDnetwork.

1/10.1103/PhysRevLett.131.140801

2/10.1038/s41534-023-00698-5

3/10.1364/OL.500406

4/10.1038/s41467-023-39219-5

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Currently,quantumcommunicationsystems,relyingonQKDandothertechnicalsolutions,havebeen

commerciallylaunchedandimplementedbothdomesticallyandinternationally.Nonetheless,commercialQKD

systemsstillencounternumerouschallengesconcerningsecurekeyrates,transmissiondistances,devicesize,and

highcosts.IncommercialQKDsystems,transmissionisoftenachievedusingprepare-and-measureQKD,which

canbefurtherclassifiedintotwotypes:continuousvariableQKD(CV-QKD)anddiscretevariableQKD

(DV-QKD).

TheadvantageofCV-QKDisthatitcouldachievehighSKRovermetrotransmissiondistancesusingtheclassical

communicationdetectionschemes.In2023,ShanxiUniversityadoptedthediscretemodulationCV-QKDto

generate2.11MbpsSKRover80km5.ShanghaiJiaoTongUniversityusedatransmitter-sidelightsource

integrationsystemtogenerate0.75MbpsSKRat50km6.TheTechnicalUniversityofDenmarkuseda

receiver-sideintegratedschemesystemtoachieve300MbpsSKRat10km7.TheUniversityofWaterloogavea

securityproofofthefinitekeylengthofthediscretemodulationCV-QKDandexperimentallydemonstratedthat

theQKDtransmissiondistancecanbelongerthan72kmwith1012keylength8.

TheDV-QKDexperimentalsystemhasundergonecontinuousdevelopment,resultingincertainenhancementsto

boththeSKRandtransmissiondistance.In2023,thegroupofappliedphysicsfromGenevarealizedaSKRof64

Mbpsover10kmviatime-binencodingQKDusingmultipixelSNSPDs9.TheresearchteamledbyUniversityof

ScienceandTechnologyofChinamadeachievementsonbothaspects,takingadvantageofmultipixelSNSPDs,a

new-recordSKRof115.8Mbpsover10kmfiberchannelwasobtainedusingadeceptivestatebasedBB84QKD

protocol10;adoptingthe3-intensitysending-or-not-sendingTF-QKD,relay-lessQKDwasrealizedovera1002km

fiberchannel.Thesestudiesdemonstratedthatcurrenttechniquescansatisfytheencryptionrequirementsforhigh

bandwidthcommunicationsandthefeasibilityinlongdistancecommunications.

ForQKDindustrialization,low-cost,mass-manufacturedandpracticalQKDdevicesarerequired.Froma

commercialutilizationperspective,thecoredevicesofquantumcommunication,includingtheQKDencoderand

5/10.1364/OL.492082

6/10.1364/PRJ.473328

7/abs/2305.19642

8/10.1103/PRXQuantum.4.040306

9/10.1038/s41566-023-01168-2

10/10.1038/s41566-023-01166-4

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decoder,aremovingtowardsminiaturizationandcost-effectiveness.NationalInformationOptoelectronics

InnovationCenterfromChinaInformationandCommunicationTechnologiesGroupCorporationdeveloped

silicon-basedpolarizationstatemodulatoranddemodulator.Relyingonthetwomodules,thequbit-basedclock

synchronizationandchip-basedpolarizationcompensationweredemonstratedover150kmdistancetoachieve

866bpsSKR11.ResearchersattheUniversityofGeneva,Switzerland,andtheInstituteofPhotonicsand

Nanotechnology,Italy,demonstratedachip-basedQKDsystemusingasilicon-basedtransmitterchipsupporting

high-speedmodulationandapolarization-independentlow-lossreceiverchipinaluminumborosilicateglass,to

achievea1.3kbpsover151km12.

2.1.2.QuantumRandomNumberGenerator

QuantumRandomNumberGenerator(QRNG)isadevicethatutilizestheprinciplesofquantumphysicsto

generatetruerandomnumbers.Unliketraditionalrandomnumbergenerators,QRNGgeneratestruerandom

numbersbasedonquantumopticalprinciples,suchasvacuumstatenoise,quantumphasenoiseoflaser

spontaneousradiation,andphotonnumberstatistics.Itstandsasthesolegenuinelytheoreticallydefensiblerandom

numbergeneratortodate,leveragingquantummechanicaluncertaintytoguaranteethegenerationofhighly

unpredictableanduncorrelatedrandomnumbers.QRNGhasimportantapplications.Incryptography,truerandom

numbersarecrucialforkeygeneration,encryptionalgorithmsandauthentication,etc.QRNGcanprovidehigher

securityagainstpasswordcracking.However,itshouldbenotedthatQRNGonlyguaranteesthetruerandomness

ofthegeneratedsequencesanddoesnotincludethesecurityofthedistributionprocess.

QRNGtechnologyiscurrentlybeingdevelopedandimproved.Manyresearchinstitutesandcompaniesare

committedtoresearchinganddevelopingmoreefficientandstableQRNGs.In2023,researchersfromajointteam

ledbyGhentUniversityexperimentallydemonstratedanultra-fastrandomnumbergenerationrateof100Gbit/s,

settinganewrecordofanorderofmagnitudeincreaseintherateofQRNGbasedonvacuumfluctuation13.

QuantumDice(UK)announcedthelaunchofitslatestgenerationofAPEXQRNGwithpost-processingrandom

numbergenerationratesofupto7.5Gbps14,whichcanalsobeintegratedintoexistinginfrastructuresandhave

highsecurityfeatures.TheGermanFederalMinistryofEducationandResearchfundedtheChip-BasedQuantum

11/10.1364/PRJ.482942

12/10.1364/PRJ.481475

13/10.1103/PRXQuantum.4.010330

14

/quantum-dice-launches-the-new-generation-of-apex-the-worlds-fastest-quantum-random

-number-generator-enabling-trusted-cybersecurity-for-enterprise-applications/

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RandomNumberDevicesproject15,whichwilldevelopahigh-speedgenerationofrandomnumbersbasedonthe

quantumphotoniceffectswithinacompactchip,meetingtheCommonCriteriaforITproductsecurity.Withthe

furtherdevelopmentofquantumtechnology,itisexpectedthatQRNGswillbeutilizedinawiderrangeof

applicationsandcontributesignificantlytoinformationsecurityandscientificresearch.

2.1.3.QuantumInformationNetwork

QuantumInformationNetworks(QIN)isacommunicationnetworksystembasedontheprinciplesofquantum

physics.Itutilizeskeytechnologiessuchasquantumentanglementmanipulation,quantumteleportation,quantum

relay,etc.,aimingatrealizingthefunctionsofquantumlong-distancecommunication,quantumcomputation,and

quantuminformationinterconnectionnetwork.QINcurrentlystandsasaresearchhotspotwithinthequantum

informationfield,representingtheforefrontofdevelopmentinbothcommunicationandcomputationforthefuture.

Inrecentyears,manycountrieshavebeenactivelypromotingtheresearchandapplicationofquantuminformation

networks.Manylaboratoriesandresearchinstituteshaveconductedanumberofexperimentstoverifythe

feasibilityandstabilityofQIN.In2023,researchersattheUniversityofScienceandTechnologyofChinaand

PekingUniversityrealized51-qubitentanglementontheZuchongzhisuperconductingquantumcomputerplatform,

usinghigh-fidelityparallelquantumgates,andrealized51-qubitone-dimensionaland30-qubittwo-dimensional

clusterstatesandachievedfidelitiesof0.637 ± 0.030and0.671 ± 0.006,respectively16.AjointteamfromPeking

Universityhasconstructedachip-basedmulti-dimensionalquantumentanglementnetwork.Thenetworkconsists

ofacentralchipconnectedtothreeendchipsbyopticalfiber,andtheentanglementrecoveryandfullconnectivity

havebeeneffectivelyrealizedattheendchipsbyusinghybridmultiplexingtechnology,whichlaysthefoundation

fortheconstructionoflarge-scaleandpracticalentanglementnetwork17.NISTconstructedtheNG-QNet(NIST

GaithersburgQuantumNetwork)testbedtocharacterizethefunctionoftheQINbasecomponents18.Theresearch

teamledbyLincolnLaboratoryconstructeda50kmthree-nodequantumnetworkexperimentalbed(BARQNET)

fortestingquantumstatesignaltransmissioncharacteristicsandcompensationmechanisms19.TheUniversityof

WaterloowillcollaboratewithEuroperesearchteamaimingatconnectingCanadaandEuropeviaaquantum

15https://www.ipms.fraunhofer.de/en/press-media/press/2023/Photonic-quantum-chip.html

16/10.1038/s41586-023-06195-1

17/doi/10.1126/science.adg9210

18/programs-projects/quantum-communications-and-networks

19/10.48550/arXiv.2307.15696

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satellitelink20.TheUniversityofFlorida,incollaborationwiththeUniversityofCalgary,Canada,proposedand

launchedaquantuminformationnetworkbasedonsatelliterelay21.Meanwhile,somecompaniesareactively

engagedinthedevelopmentofQIN.Forexample,Qunnect,incooperationwithNewYorkUniversity,tested

successfullya16-kilometerQINlinkusinghighlyentangledquantumphotons22.Theseeffortsandcollaborations

areexpectedtopromotethedevelopmentandapplicationofQIN.

2.2.StandardizationActivitiesforQKD

Inrecentyears,majorstandardizationorganizationshaveactivelycarriedoutthepreparationofQKDrelated

standards,includingtheChinaCommunicationsStandardizationAssociation(CCSA),theChinaCryptography

IndustryStandardizationTechnicalCommittee(CSTC),andtheNationalInformationSecurityStandardization

TechnicalCommittee(TC260);Internationally,therearetheInternationalOrganizationforStandardization(ISO),

theInternationalTelecommunicationUnion(ITU),andtheEuropeanTelecommunicationsStandardsInstitute

(ETSI).Thecontentofthepreparationhascoveredterminologydefinitions,applicationscenariosandrequirements,

networkarchitecture,equipmenttechnicalrequirements,QKDsecurity,testingandevaluationmethods,andother

aspects.

2.2.1.ChineseStandardizationProgress

ChinaCommunicationsStandardizationAssociation（CCSA）

TheChinaCommunicationsStandardizationAssociation(CCSA)isastandardizationorganizationengagedinthe

fieldofinformationandcommunicationtechnologyinChina,conductingresearchoncommunicationstandard

systems.CCSAhasestablishedthe7thSpecialTaskGroup(ST7)forQuantumCommunicationandInformation

Technology,whichincludestwosubworkinggroups:theQuantumCommunicationWorkingGroup(WG1)and

20

https://uwaterloo.ca/news/science/connecting-canada-and-europe-through-quantum-satellite?utm_source=miragenews&u

tm_medium=miragenews&utm_campaign=news

21/prapplied/abstract/10.1103/PhysRevApplied.20.024048

22

/about/news-publications/news/2023/september/nyu-takes-quantum-step-in-establishing-cutting-edg

e-tech-hub-in-.html

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theQuantumInformationProcessingWorkingGroup(WG2).ST7hasinitiated25standarddevelopmentprojects

intermsofterminologydefinition,applicationscenariosandrequirements,networkarchitecture,equipment

technicalrequirements,QKDsecurity,andtestingandevaluationmethods.Amongthem,thenationalstandard

GB/T42829-2023“Basicrequirementsforquantumsecurecommunicationapplications”wasofficiallyissuedin

August2023.12othercommunicationindustrystandardshavealsobeenofficiallypromulgatedandimplemented:

YD/T4632-2023Technicalrequirementsforquantumkeydistributionandclassicalopticalcommunicationco

fibertransmission

YD/T3835.2-2023Testmethodsforquantumkeydistribution（QKD）systemsPart2:QKDsystembasedon

Gaussianmodulatedcoherentstateprotocol

YD/T4410.1-2023QuantumKeyDistribution(QKD)NetworkAkInterfaceTechnicalRequirementsPart1:

ApplicationProgramInterface(API)

YD/T3834.2-2023Technicalrequirementsforquantumkeydistribution(QKD)systemsPart2:QKDsystems

basedonGaussianmodulationcoherentstateprotocol

YD/T4303-2023Technicalspecificationofquantumsecurecommunicationapplicationequipmentbasedon

IPSecprotocol

YD/T4302.1-2023Technicalspecificationforquantumkeydistribution(QKD)networkmanagement—

Part1:NMSsystemfunction

YD/T4301-2023Quantumsecurecommunicationnetworkarchitecture

YD/T3907.2-2022KeycomponentsandmodulesforQuantumKeyDistribution(QKD)basedonBB84

protocol—Part2:Singlephotondetector

YD/T3907.1-2022KeycomponentsandmodulesforQuantumKeyDistribution(QKD)basedonBB84

protocol—Part1:Lasersource

YD/T3907.3-2021KeycomponentsandmodulesforQuantumKeyDistribution(QKD)basedonBB84

protocol-part3:QuantumRandomNumberGenerator(QRNG)

YD/T3835.1-2021TestmethodsforQuantumKeyDistribution(QKD)system-Part1:DecoystateBB84

protocolQKDsystem

YD/T3834.1-2021Technicalrequirementsforquantumkeydistribution(QKD)system-Part1:Decoystate

BB84protocolQKDsystem

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ChinaCryptographyIndustryStandardizationTechnicalCommittee（CSTC）

QKDtechnologyinvolvesthegeneration,management,anduseofpasswords.TheChi