国际清算银行-功能性中央银行数字货币（CBDC）架构的高级技术要求（英）

BISConsultativeGrouponInnovationandtheDigitalEconomy(CGIDE)

Report

High-leveltechnicalrequirementsforafunctionalcentralbankdigitalcurrency(CBDC)architecture

December2023

BISRepresentativeOfficefortheAmericas

CGIDE–High-levelrequirementsforaCBDCarchitecture

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ThispublicationisavailableontheBISwebsite

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©BankforInternationalSettlements2023.Allrightsreserved.Briefexcerptsmaybereproducedortranslatedprovidedthesourceisstated.

ISBN978-92-9259-726-9

CGIDE–High-levelrequirementsforaCBDCarchitecture

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Tableofcontents

Foreword 4

Executivesummary 5

Introduction 7

1Background 7

1.1CBDCpolicyobjectivesandconsiderations 8

1.2ConsiderationsforthetechnologicaldesignofCBDCs 9

1.3ExperiencesinthedesignandadoptionofCBDCs 11

2High-levelrequirementsforaCBDCarchitecture 13

AnnexA:MembersoftheTechnicalTaskForceoftheConsultativeGrouponInnovationandtheDigital

Economy 18

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Foreword

Centralbankdigitalcurrencies(CBDCs)aredigitalpaymentinstrumentsissuedbycentralbanks.Theyentailanewpublicinfrastructurethatoffersmanydifferenttechnicaloptionsandfunctionalities.Aseachcentralbankexploresthefeaturesthataremostrelevantforthepolicygoalsoftheirownjurisdiction,itcanbeveryhelpfultoshareexperienceswithpeerinstitutions.ThismaybeparticularlyrelevantinthelightoffutureinteroperabilitybetweenCBDCs.Inthiscontext,thisreportintroducesaseriesofhigh-leveltechnicalrequirementsforaretailCBDCproofofconceptagreedbytheBISConsultativeGrouponInnovationandtheDigitalEconomy(CGIDE).TheserequirementsmayserveasabasistodevelopfunctionalCBDCsolutions,potentiallyworkingasareferenceformembercentralbanksintheAmericasandaroundtheworld.

TheCGIDEwaslaunchedinFebruary2020tomeetthedemandforgreatercooperationintechnologicalinnovationandthedigitaleconomybyBISmembercentralbanksintheAmericas.ItreportstotheConsultativeCouncilfortheAmericas(CCA),whichbringstogetherthecentralbankGovernorsofArgentina,Brazil,Canada,Chile,Colombia,Mexico,PeruandtheUnitedStates.Thisgroupprovidesaforumwhereseniorcentralbankofficialscancooperatetowardsthefollowingobjectives:

a.Analysinganddevelopingpublictechnologicalinfrastructuresgearedtowardstacklingcommonshortcomingsinallparticipatingjurisdictions.

b.Promotinganenvironmentsuitabletoopenbanking,potentiallythroughthedevelopmentofkeyapplicationprogramminginterfaces(APIs).

c.Analysingtheimplicationsofthesepublictechnologicalinfrastructuresintermsofmarket

structureandregulatoryimplications.

ThisreportwaspreparedbyatechnicaltaskforceofcentralbankexpertswhoparticipateintheCGIDE.ItsmainpurposeistoopenaconversationaroundtechnicalconsiderationsinthedesigningofaCBDC.Thereportseeksfeedbackfromcentralbanksandthepubliconthehigh-levelrequirementsforafunctionalproofofconceptforaretailCBDCarchitecture,proposedbytheCGIDE.ItalsoaimstoserveasausefulgeneralreferenceforcentralbanksconductingresearchonCBDCorseekingtodeveloptheirownCBDCinitiatives.Commentsarewelcomeandshouldbeaddressedto

CGIDEreport@.

OthónMoreno

ChairoftheTechnicalTaskForce

BankofMexico

RenatoDiasdeBritoGomes

ChairoftheCGIDE

CentralBankofBrazil

AlexandreTombini

ChiefRepresentativeforthe

Americas

BankforInternationalSettlements

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Executivesummary

Centralbankdigitalcurrencies(CBDCs)aredigitalpaymentinstrumentsissuedbycentralbankswiththepotentialtorevolutionisethefinanciallandscape.CBDCscouldofferarangeofbenefitstobothindividualsandbusinessesandthewholeeconomy.Byleveragingadvancementsintechnology,CBDCscanenhancepaymentefficiency,promotefinancialinclusion,increasesecuritywhilepreservingprivacy,andenablenewfinancialfunctions,forinstancewithassettokenisationandtrading.CentralbanksworldwideareactivelyexploringCBDCs,consideringvariousdesignoptionsandtechnologicalfeatures.Thisreportoutlineshigh-leveltechnicalrequirementsforaretailCBDCarchitecture,coveringmodulardesign,corefunctions,operationalandcyberresiliencerequirementsandthird-partyservices.ThereportaimstocontributetotheresearchandexplorationofCBDCs,anddoesnotrepresentapolicypositionfromCGIDEmembersandobserversortheircentralbanksonCBDCdesign,issuanceoradoption.ThetechnicalrequirementsoutlinedhereconstitutethefoundationfortheCBDCarchitecturetobeproposedbytheCGIDEandarenotintendedastechnicalstandardsforCBDCsmoregenerally.

TheConsultativeGrouponInnovationandtheDigitalEconomy(CGIDE)launchedatechnicaltaskforce(TTF)inMay2022tocreateaproposalforaretailCBDCarchitecture,guidedbyhigh-leveltechnicalrequirementsendorsedbyCGIDEmembers.TheTTFaimstodeliverthreeoutputs:(i)adefinitionofhigh-leveltechnicalrequirementstoidentifycorefunctionalityandnecessaryelements;(ii)abusiness-levelflowdiagramforthecorefunctionality;and(iii)atechnical-levelflowdiagramwithinfrastructurecomponentsforCBDCimplementation.Thisreportispartofdeliverable(i).ItistheculminationofaseriesofdiscussionsamongTTFmembersonCBDCobjectives,policyconsiderationsandtechnologicalfeatures.TheCGIDETTFalsoparticipatedinwebinarsandworkshopstofurtherexplorethedevelopmentandimplementationofCBDCs.

BasedonthesediscussionsandpreviousworkbytheBIS,CGIDEmembersfocusedonthreepolicygoalsthatcanbesupportedbyCBDCs.First,CBDCscanpromotefinancialinclusionbyofferingalternativedigitalpaymentmethodsandprovidingaccesstofinancialinstrumentsandpaymentservicesforpeoplewithoutbankaccountsorthoseseekingalternativestobankaccountsandcash.Second,CBDCscanincreaseefficiencyandcompetitioninthefinancialsystembyprovidingalow-costpublicinfrastructurethroughwhichbanks,non-bankfinancialinstitutionsandfinancialtechnologyfirmscanofferbothpaymentandotherfinancialservices.Thiscanlowerentrycostsfordeposit-taking,creditorinsuranceactivities.Third,CBDCscanpromoteinteroperability,reachingabroaderaudienceandinterconnectingwithexistingpaymentservices.However,policyconcernsrelatedtothepotentialimpactonfinancialinstitutionsandtheneedtopreserveprivacyinfinancialtransactionsstillneedfurtherdiscussion.

TheCGIDEexploredseveraltechnologicalconsiderationsforretailCBDCs.Sometechnologicalchoicesincludedwhethertoreuseexistingpaymentsystemsorbuildfunctionalityfromscratch;account-basedversustoken-basedsolutions;centralisedsettlementversusdistributedmodels;embeddedpayment-versus-payment(PvP)anddelivery-versus-payment(DvP)functionalities;keymodulesnecessarytodefineacompleteCBDCplatform;andprivacyanddataprotection.OtherkeyaspectsforthedesignofaCBDCplatformincludedscalability,technologicalindependenceanddocumentationdistributionstrategies.

TheCGIDETTForganisedaseriesofwebinarsandworkshopstofacilitatediscussionsonthedesignandimplementationofCBDCs.Thesesessionsincludedpresentationsfromvariouscentralbanksandorganisations,whichsharedtheirexperiencesandinitiativesrelatedtoCBDCs.Thepresentationscoveredawiderangeoftopics,includingprojectsandprototypesbytheBISInnovationHub,R3’sCordaplatformformulti-partyworkflows,Uruguay’se-pesopilotandProjectHamilton,bytheFederalReserveBankofBostonandMIT,whichallexploredthetechnicalfeasibilityofretailCBDCs.DuringtheCGIDEin-personmeetingheldinMarch2023,membersalsodiscussedtheexperienceoftheCentralBankofTheBahamasintheadoptionoftheSandDollar.Inaddition,taskforcemembersdiscussedcomplementaryoptionstoenhancepaymentsystems,suchasBrazil’sfastretailpaymentsystemPix,Mexico’sCobroDigital(CoDi)forinstantpayments,India’sopenbankingstrategyandtheUnitedKingdom’sopenbanking

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implementation.Thediscussionsprovidedvaluableinsightsintodifferentapproaches,challengesandopportunitiesinCBDCimplementationandhighlightedconsiderationsrelatedtotechnology,governance,privacyandperformance.

Thehigh-leveltechnicalrequirementsforafunctionalretailCBDCproofofconcept,tobedevelopedbytheTTF,aregroupedintofivecategories:(i)modulardesign;(ii)corefunctions;(iii)operationalrequirements;(iv)cyberresiliencerequirements;and(v)requirementsrelatedtothird-partyservices.Basedonthesehigh-levelrequirements,theCGIDETTFwillpresentaproposalforaCBDCarchitecture.Theinitialstageofthisproposalwillfocusontechnologicalfeaturesconcerningclearingandsettlement.Regardingthemodulardesign,theTTFprioritisesabalance-keepinglayerthatallowsforthecreation,custodyanddestructionofCBDCs,withafungibleapproach.Additionally,thedesignwillincludethepossibilitytoissuenon-fungibletokens(NFTs)forspecificusecases.TheproposedCBDCarchitecturewillalsofacilitateseamlessintegrationwithexistingpaymentsystemsandleverageAPIsfordataexchangeandpaymentinitiation.CorefunctionstobeconsideredincludecentralisedissuanceanddestructionofCBDCs,aswellaspaymentinitiationfeaturesfacilitatedbyanAPI.Theoperationalmoduleemphasisesscalability,userexperienceandthedefinitionoftheattributefunctionmatrix.Cybersecurityisalsoatoppriority,withrequirementssuchasencryption,dataconfidentiality,technologicalindependenceandauditabilitytoprotecttheintegrityandconfidentialityoftheCBDCarchitecture.Allotherrequirements,includinginteroperability,cross-borderpaymentfunctionalities,riskmanagementandbusinesscontinuityissuesaredeemedcrucialforacomprehensiveCBDCarchitecture.Theserequirementswillbeaddressedinthesecondstageoftheproject,scheduledforthesecondquarterof2024.

Together,theserequirementspresentachallengeforcentralbanksinthedesignofCBDCs.However,throughcollaborativeefforts,centralbankscandesignarchitecturesthatmeettheseneedsandestablisharobustfoundationforfutureinnovation.TheCGIDEwillcontinuetocollaborateclosely,workingtowardsthedesignofaCBDCarchitecturethateffectivelyaddressesthetechnologicalprioritiesofCCAcentralbanks.

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Introduction

Centralbankdigitalcurrencies(CBDCs)aredigitalpaymentinstrumentswhicharedenominatedinthenationalunitofaccountandareadirectliabilityofthecentralbank

(GroupofCentralBanks(2020))

.Theyrepresentanewformofcurrencythatcanbeusedforelectronictransactionsbyfinancialinstitutionsand/orhouseholdsandbusinessesandcanbestoredandexchangeddigitally.MostcentralbanksaroundtheworldareexploringCBDCs,andmorethanhalfofthemareconductingconcreteexperimentsorworkingonapilot(KosseandMattei(2023)).ThemotivationsbehindthislieinCBDCs’potentialtosupportdifferentpolicygoals.Forinstance,CBDCscanimprovetheefficiencyofpayments,reducingthecostandtimeoftransactions.CBDCscanalsoincreasefinancialinclusion,makingiteasierforunbankedandunderbankedpopulationstoparticipateinthefinancialsystem.Additionally,CBDCscanoffergreatertransparencyandsecurity,ascentralbankscandeterminethedegreeofanonymityortraceabilityoftransactions.Theymayalsopromoteinteroperabilitywithexistingpaymentinstrumentsandenablenewfunctionalities.

Dependingonaneconomy’sspecificneedsandobjectives,centralbankshavedifferentdesignoptionsandtechnologicalfeaturesavailableintheirCBDCexploration.TheseconsiderationsincludetheunderlyingtechnologyusedforCBDCimplementation,thedifferentlayerscomprisingthecoreCBDCinfrastructure,thedegreeofanonymityortraceabilityoftransactions,thedegreeofinvolvementoftheprivatesectorintheCBDCinfrastructureandtheinteroperabilityofCBDCswithexistingpaymentsystems.

Inthisreport,theCGIDETTFpresentsaseriesofhigh-leveltechnicalrequirementsforaretailCBDCarchitecturethatitwilldevelopinthenextstage.Thesehigh-levelrequirementsareclassifiedintofivecategories:(i)modulardesignwithalayeredinfrastructure;(ii)corefunctions;(iii)operationalrequirements;(iv)cyberresiliencerequirements;and(v)otherrequirementsrelatedtoservicesprovidedbythirdparties.ThereportalsoprovidesbackgroundontheworkundertakenbyCGIDETTFtodateandthestepsforward.

AsinpreviousreportsoftheCGIDE,theworkoftheCGIDETTFonCBDCsaimstoserveasageneralreferenceforindividualcountriesconductingresearchonCBDCsorplanningtoimplementaCBDCsolution.TheoutputoftheCGIDETTFwouldnotimplyapolicypositionfromanyCGIDEmemberorobserverortheirrespectivecentralbanks.

Thisreportpresentstwosections.Section1describesthebackgroundworkconductedbytheCGIDETTFtoidentifythetechnicalrequirementsthattheCBDCproofofconceptwillinclude.ThissectioncontainsasummaryoftheCGIDEdiscussionsonCBDCpolicyobjectivesandimplicationsandtechnologicalconsiderations,aswellassomeexperienceswithCBDCissuanceandadoption.Finally,Section2presentstheproposedhigh-leveltechnicalrequirementsforaCBDCarchitecture.

1Background

TheCGIDETTFwascreatedinMay2022todesignaproofofconceptforaretailCBDCarchitecture,basedonthehigh-levelrequirementsvalidatedbyCGIDEmembers.TheobjectiveofthisexerciseistocontributetothediscussionandtheCBDCresearchinitiativesateachCCAcentralbank.TheproposedarchitectureaimstoserveasareferenceanddoesnotconstituteanofficialpositionfromCGIDEmembersorobserversortheircentralbankswithrespecttothedesign,launchoradoptionofCBDCs.TheTTFwillproducethreeoutputs:(i)aprioritisationoftherequirementstoidentifycorefunctionalityandthenecessaryauxiliaryelementstosupportit;(ii)abusiness-levelflowdiagramforthecorefunctionality;and(iii)atechnical-levelflowdiagramofthecorefunctionalitywithpiecesofinfrastructurerequiredfortheimplementationoftheCBDC(eghardware,softwaremodules).TheprioritisationoftherequirementswaspresentedbytheTTFtotheCGIDEduringthemeetingsheldinSeptemberandOctober2022.Thisreportpresentsthehigh-

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levelrequirementsforthedefinitionofaretailCBDCarchitecture.Basedontheserequirements,theCGIDETTFwillworkondeliverables(ii)and(iii).

Priortodefiningthehigh-levelrequirements,CGIDEmembersexchangedviewsontheobjectivesandpolicyconsiderationsofCBDCs,andtechnologicalfeaturesofCBDCdesignintheirjurisdiction.TheCGIDETTFalsoparticipatedinseveralwebinarsandworkshopstodeependiscussiononthedevelopmentandimplementationofCBDCs.Thesediscussionsservedtoshareknowledgeandcontributedtoacommonunderstandingofmanykeyconceptsthatwillbediscussedingreaterdepth.

1.1CBDCpolicyobjectivesandconsiderations

CGIDEmembersagreedonthreemainpolicygoalsthatcanbesupportedbyCBDCsandonwhichtheTTFfocused.

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First,CBDCscouldfosterfinancialinclusion,byprovidinganalternativemeansofdigitalpayments.CBDCshavethepotentialtobridgetheunbankedandunderbankedpopulationandthefinancialsystem.Theycouldbroadenaccesstofinancialinstrumentsandpaymentservicesforpeoplewithoutbankaccountsorwhoareseekingalternativestobankaccountsandcash.ByextendingthefunctionalitiesofCBDCs,theycouldalsobeusedtosupportfinancialservices(beyondpayments)thataretailoredtotheneedsofthepopulation.

Second,CBDCscouldincreaseefficiencyandcompetitioninthefinancialsystem.Theycouldprovidealow-costpublicinfrastructurethroughwhichbanks,non-bankfinancialinstitutionsandfinancialtechnologyfirmscouldofferbothpaymentandotherfinancialservices.Forexample,entrycostsrelatedtodeposit-taking,creditorinsuranceactivitiescouldbelowered,asnewfinancialserviceproviderscompeteonalevelplayingfieldwithincumbentinstitutions.

Third,CBDCscouldpromoteinteroperability.Dependingontheirtechnologicalfeatures,CBDCscouldreachabroaderaudienceandinteroperatewithexistingpaymentservices.InteroperabilitywouldbenecessarytoensurethatpeoplewithandwithoutCBDCholdingscouldinteractwitheachother.

Asanewpaymentinfrastructure,CBDCsoffermanyoptionstosupportthesepolicygoals.Countriesareatdifferentstartingpoints.Somearemoreadvancedinretailfastpaymentsystemsortheadoptionofdigitalpayments,whileothersareatanearlierstage.Still,theconsensusintheCGIDEisthataCBDCwouldbeacomplementtoexistingpaymentrails.

ThesuccessofCBDCsinsupportingthesepolicygoalswilldependontheirwideadoption.Onemeasureofsuccesscouldbethedegreeofadoptionbythepopulation,andhowmuchitchangesthefinancialandpaymentsecosystem.Otherindicatorsofsuccesscouldbetheimpactonaccesstotransactionaccountsortofinancialservicesbeyondpayments,paymentcostsintheeconomy,thedegreeofcompetitionandwhetheraCBDCenablesmoreinteroperablefinancialservicesandresponsibleinnovation.

AmongthepolicyconcernsrelatedtotheintroductionofaCBDCarehowitwouldinteractwithfinancialinstitutionsandhowitwouldaffectprivacyinfinancialtransactions.First,aCBDCcouldpotentiallyaffectfinancialinstitutionsbydisplacingdeposits(disintermediation).IfCBDCswereintermediatedbyfinancialfirms,andiftheydidnotpayinterest,thiscouldbelessdisruptive.FinancialfirmswouldstillbethemainprovidersofcreditandsavingsservicesandcouldleadinthedistributionoftheCBDC.Second,userprivacyisacrucialconsiderationforallpaymentinstruments,includingCBDCs.Inthislight,aCBDCshouldpreserveorenhancethecurrentlevelofprivacyinfinancialtransactions.ACBDCshouldbedesignedwithfirmtechnologicalandinstitutionalsafeguardsondataprivacy.

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1Thesepolicygoalsarebroadlyapplicableincountriesaroundtheworld,buttheyapplyparticularlyintheAmericas.SeeAueretal(2020),Aueretal(2021)andKosseandMattei(2022)foradiscussionofthemotivations,approachesandeconomicimplicationsbehindCBDCs.

2Thiscanbepromotedthroughbothtechnologicaldesignandinstitutionalframeworks.SeeUhligetal(2023).

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1.2ConsiderationsforthetechnologicaldesignofCBDCs

TheCGIDEdiscussedthetechnologicalfeaturesofCBDCsbasedonthepreviouspolicyobjectivesandconsiderations.Theinsightsfromthesediscussionscontributedtodefiningthehigh-levelrequirements.Someofthetechnologicalconsiderationsincluded:

−Reusingfunctionalityfromexistingpaymentsystemsvsbuildingfunctionalityfromscratch.Ononehand,reusingexistingtechnologiescouldspeedupthetimerequiredtodevelopacompleteCBDCsolution.Forinstance,real-timegrosssettlement(RTGS)systemsrunbythecentralbankcouldbepartofaCBDC’ssettlementlayer,orcreditnotificationspreviouslyimplementedonanRTGScouldbetheinitialimplementationforatokenoraccount-basedlayer.Someofthedrawbacksofthisoptionincludethegenerationofasinglepointoffailure,thelimitationsofsomesystemsintermsofavailability,andscalability.Additionally,thereareconcernsrelatedtotheoperationofpaymentsystemsbytheprivatesector.Ontheotherhand,aCBDCsystemcouldbedevelopedwithfullfunctionalityfromscratchinsuchawaythatitcaninterconnectwiththeexistingsystem.Theadvantagesofthisoptionincluderesilienceoftheecosystem,flexibilityintermsoftechnologicalcapabilitiesandnolegacyinfrastructure.However,producinganewsystemtakeslongertoimplementandrequiresadditionalinvestment.Thesetwoviewscouldbeaccommodatedbydesigningamodulararchitecturethatconsidersthefunctionsofapaymentsystemasexogenous.Thiswouldmeanthatitcansupportapre-existingsettlementmechanismoranewlydevelopedone.ThisconsiderationalsoappliestotheenduserlayerwherecentralbankswillhavetomakedesignchoicesrelatedtothedevelopmentofnewdevicesorappsforCBDC,ortheuseofexistingappsandpaymentdeviceswithCBDCcapabilitiesembeddedinthem.

−Account-basedvstoken-basedsolution.Thisconcernswhethervalidationisbasedontheidentityofanindividual(account-based)orontheveracityoftheinstrument(token-based).Whiletheformerhasclearadvantagesinsomecases,

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theCGIDEconsidersthatatoken-basedapproach

couldbedesirableforpeer-to-peertransactions.Whileprogrammabilityfeaturescanbeachievedwithbothapproaches,atoken-basedsolutioncouldofferamoreextensiveandflexibleprogrammableinfrastructureandfacilitatetheuseofsmartcontracts.Theremaybesolutionsthatallowforthebenefitsofdigitaltokens(andtokenisation)whilepreservingsoundidentification.

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−Centralisedsettlementvsdistributedpermisionlessmodel.TheCGIDEmembersagreeonthedifficultiesassociatedwithdecentralisedpermissionlessmodels.Forexample,thesemodelsrequireaconsensusmechanismtovalidatetransactions.However,duetotheirdistributednature,thereistheriskthatparticipantsinvolvedinthenetworkcouldcolludetomanipulatethesystem.Intheabsenceofsufficientoversight,governancemechanismsorregulatorycontrol,thiscouldresultinnegativeoutcomes.Forthisreason,distributedpermissionlessmodelsalsorequirethedefinitionoftheincentivestructure(technological,monetaryorregulatory)todiscouragecollusionamongparticipants,andanotarylayerabletobanparticipants.

Inturn,centralisedorpermissionedledgermodelsrequirethedefinitionofredundancies,

resilienceandbusinesscontinuityrequirementsthatwouldreducetherisksfromasinglepointoffailure.Thesemodelshavethepotentialtohostanopenfinancelayerbuiltontopofthetransactionlayer,allowingfinancialserviceproviderstoofferlast-milepaymentservicestofinalusers.

3SeeBIS(2021a)foradiscussionoftheadvantagesofaccount-basedCBDCvariants,whichincludecombatingillicitactivityandthepossibilityofestablishinginterestratetieringandcapsonholdingsintheCBDCdesign.

4Digitaltokensareunitsofvaluethatexistindigitalformonablockchainordistributedledger.Theyaretherepresentationofanassetandcanbecreated,issuedandtransferredelectronically.Tokenisationreferstotheprocessofrecordingclaimsonfinancialassetsthatexistonatraditionalledgerontoaprogrammableplatform.SeeAldasoroetal(2023).

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Relativetodistributedpermissionlessmodels,centralisedorpermissionedledgermodelsoffersomeadvantages.Firstly,theyallowforahigherlevelofcontrolthatcanbemaintainedbythecentralbank.Theyalsoenabletheenforcementofstrictanti-moneylaundering(AML)andknowyourcustomer(KYC)requirements.AsfinancialinstitutionsshouldadoptandcomplywithAMLandKYCregulations,thedesignofaCBDCneedstofacilitateadherencetotheserules.Consideringthesetrade-offs,theCGIDEagreedonaflexibleapproachthatenvisagessolutionsalternativetoafullycentralisedmodel,withthepossibilitytodesignpermissionedledgersthatexhibitsomedecentralisation.Thisapproachaimstostrikeabalancebetweencentralisedcontrolandbroaderaccesstospecificinstitutions.

−Embeddedpayment-versus-payment(PvP)anddelivery-versus-payment(DvP)functionalities.TheintegrationofPvPandDvPfunctionalitiesoffersaseamlesssettlementprocessthatensuresbothcounterpartiesfulfiltheirobligationssimultaneously.Thiscanbeachievedthroughachoicebetweenadistributedapproachoracentralisedplatform.Inacentralisedmodel,aplatformoverseenbythecentralbankcouldemployanalgorithmtomatchbidwithaskpositionstoformprices.Suchanalg