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WHITEPAPER
EvolvingEdgeComputing
Contents
1WhyEvolveEdgeComputing?
2Vision
2.1EdgeVersusCloud
2.2Why‘CloudLike’inEdgeComputing?
2.3What’schanginginIoT/EdgeComputing?
2.4ChallengestoOvercome
2.5Summary
3.6Bibliography
WHITEPAPER2
1WhyEvolveEdgeComputing?
Edgecomputingisatermthathasbeeninuseforalongtime.Throughout
theindustry,therearemanyreferencestoedgeandmanypre-conceptions
aboutwhatthatmightmean.Theterm‘edge’istypicallyusedfordevicesthatexistontheedgeofanetworkandcancoveraplethoraofusecases,rangingfromtherouterinyourhouse,asmartvideocamerasurveyingaparkinglot,toacontrolsystemmanagingarobotonaproductionlineinasmartfactory.Itishardlysurprisingthenthat‘edge’isaconfusingtermwithsomanyuse
caseexamplestochoosefrom.
So,whatishappeningthatmeansthatArmiscallingforanevolutioninedgecomputing?Thispaperexaminestheconvergenceofseveralmarkettrends
thatpresentnewchallengesandopportunitiesinthisspaceandrequireustorethinkthewayforward.
Firstly,edgedevicesarebecomingconnectedtocloudservicessuchthattheyaregenerallylocatedclosetothesourceofdata.Inturn,theygenerateinsightthatfeedsnewdigitaltransformationservicesthatarehostedinthecloud.
Inthiscontext,wedefine‘thecloud’asbeingacentrallylocatedcomputeresource,typicallydatacenterbased,runninghigh-levelbusinessservices.
Theseservicesconsumeinsight(data)fromavastnumberofremotely
locatededgedevices.Asthiscloud-connectedtrendaccelerates,weseea
deepeningofthe‘relationship’betweencloudandedgedevices,suchthat
thecentrallylocatedservicesconsumingthedatahaveanever-increasing
amountofcontrolovertheedgedeviceswiththeaimofdrivingeverhigh
levelsofefficiencyinhowthesenetworksaredeployed.Althoughtheedgeisdistinctlydifferenttocloudcomputeresources,weexpecttoseedevelopersincreasinglybeingabletodevelopapplicationsatahighlevelthatare‘pushedout’totheedge,enablingdatainsightstoberefinedandtunedforvery
specificusecases.
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Forthepurposesofthispaper,wefocuson‘frictionlessdevelopment’
asatermthatembraceshigh-levelworkloadswithhardwareabstraction,whileallowingthedevelopertoexploitthefullbenefitsoftheunderlyinghardware.
EvolvingEdgeComputing-EssentialIngredients
Developersneedtofocusonvalueadd,embracestandardsandmaximizere-use
‘Cloud-like’
Agileinnovationwithrapid
re-useacrossdevices.
Securityatscale
Trusteddevicesandtrusted
SWwithsecurelifecycleand
regulatorycompliance.
ModularSW
Complexmulti-vendorSWstacksthatworktocommonbestprectices.
Heterogeneity
Hardwareefficiencytuned
tospecificusecases.
Collaborative
Newmodelsof
collaborationtounlockthepotentialofedgecompute.
Eliminateneedlessfragmentation
Rightbalanceof
standardsandinnovation.
Eliminateunnecessarynon-differentiating
perplatformoverheadson-Arm.
Eachpartofthevaluechainfocuseson
value-addanddifferentiation.
FIG.1
EvolvingEdgeComputing–EssentialIngredients
Secondly,weseeahugeshiftinthemarkettodrivinginsightthrough
artificialintelligence.Typically,thismeanspushingAImodelsouttoedgedevicessotheycandelivertheinsightneededforbusiness-levelservices.
Finally,thesedevicesneedtobemanagedinasecureway.Asdescribedlaterinthepaper,emergingregulationsmandatesoftwaresecurityand
guaranteedupdates,makingitincreasinglyimportanttoconsiderthefullsecuritymodelofedgecomputing.Whendeployedatscale,edgedevicesareperformingacriticalroleinthedeliveryofhigh-valueservicesand
makingthemmorevulnerabletobadactormanipulation.
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Secureidentityandsecurelifecyclemanagementarecriticalconsiderationsforabest-practiceedgecomputingapproach.
Inthecontextofthispaper,edgecomputingandsubsequently,edgeAI,
typicallyencompassescompute-richdevicesthatcanbeprogrammedin
high-levelabstractedlanguagesthatmakethemaccessibletoabroadrangeofdevelopers.FromanArmarchitectureperspective,thiscurrentlyrelies
onArmCortex-Aastheprincipalprocessingelement.Theabilitytosupportcompute-intensiveworkloadsandrichoperatingsystems,includingLinux,allowsproductsbasedonCortex-Abasedtoaddressthewidestpossible
setofusecases.
WecanexpectmanyedgeAIusecasestobepower-consumptionandcostsensitive,sothereisanongoingneedtobalancetheseaspectsacrosstheecosystem.Withthisinmind,wealsolookattheneedforheterogeneity,
i.e.,movingcompute-intenseworkloadstospecialisttypesofcomputethatofferamorebalancedapproach.
2Vision
Asuse-casecomplexityandthescaleofsmartconnectededgedevices
deploymentgrows,almostexponentially,sometechnologiesusedin
cloud-native
[1]
solutionsarebeingembracedinedgecomputing.Weseeafuturethatempowersthenextgenerationofapplicationdeveloperswithfrictionless‘cloud-like’developmentflowsthatfuelcollaboration,maximizere-use,acceleratetimetomarket,andreducethetotalcostofownership
onArm.TherapidadvancementofAIusecasesisexpectedtofuelmostofthegrowthintheedge(oredgeAI)market,withinferencebeingdeployedatscaleacrossmultiplearchitectures.
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Thisrapidshiftinedgecomputerepresentsseveralchallenges,whichArmbelievesnecessitateanevolved,best-practiceapproachtoedgecomputingtoenabletheintelligentedgethrough:
—Re-useofsoftwarecomponents:Applicationsareakeydifferentiator.Theavailabilityandre-useofthecoreunderlyingstackiscriticalas
developerswishtofocusondifferentiationandmaximizere-useelsewhere.
—Embracingheterogeneitythroughabstractionofthecomplexityofdifferentiatedhardwarewithacommonsoftwareecosystem:
Devicesareuse-caseoptimizedbasedoncost,power,andperformance,drivinghybriddevicearchitectures(CPU/GPU/NPU/ISP,andsoon).
Thecommonsoftwareecosystemneedstoprovideanintegratedviewofthesystemwithlevelsofabstractionthatreducecomplexity.
—Genericabstracteddevelopmentflowsthatfuelcollaboration,speedtimetomarket,lowertotalcostofownershipandmaximizere-use:
Usecloud-nativederivedmethodologies,suchascontinuousintegration/continuousdeployment(CI/CD),todevelop,testapplications,anddeployefficientlytotargethardware.Developmentflowefficiencyiskeyinboththedevelopmentphase,aswellasinlong-tailmaintenanceoncethe
applicationisdeployed.
—Securityatscale:Thisisachievedthroughfrictionlesssecurelifecyclemanagementandregulatorycompliancetoreducetotalcostof
ownershipforthedeployedlifetimeofthedevice.
2.1EdgeVersusCloud
Beyondhardwareconstraints,thereareseveralkeydifferencesbetween
edge[
2
]andcloudasoperationalenvironments.Edgenodesanddevicesarepurpose-builtwithdifferentcostconstraints,resultinginmanydifferentconfigurationsdeployedovermultiplegenerationsofunderlyinghardwarecomponents.
WHITEPAPER6
Nodesdifferinhardwareresources,suchasCPUarchitecture,
micro-architecture,corecount,memory,storage,connectivity(latencyandbandwidth),peripherals,andaccelerators.Additionally,edgenodes
andgatewaysaremorelikelytorequiredynamicfrequencyscaling(eitherbecauseofbatteryconservationorthermalthrottling).Thishighdegreeofhardwareheterogeneityhasimplicationsondeployment,wheremultipleversionsofanapplicationmayberequiredtosupportdevicedifferences.
CloudNativeCloudEdge/IoTEmbedded
Highperformancecloudnativecompute
Optimisedcompute
High-performance,portableworkflowsUse-caseoptimizedefficiency,targetedworkflows
Deploy,
maintain
and
enhance
Deploy,
maintain
and
enhance
Deployandmaintaine.g.SW
updates
Deployandforget
Deploy,
maintain
and
enhance
Cloud-nativeworkflowscales
downtoedgeserver,hardwareabstractedandportable,butstill‘inthecloud.’
Embeddedsystemsscale-up,becomingsecure,connected,supportingsoftware
updatesandtakingonmoreofacloud-typedevelopmentflow.
FIG.2Organicgrowthandphysicalconstraints,suchaslocationanddifficult
CloudtransitiontoEdgeorcostlyreplacement,requiremultiplegenerationsofnodestocoexist,
leadingtodifferentSKUsofthedevicesupportedwiththesameapplicationsoftwareduringthesystem’slifetime.
Theedgeislikelytohaveahigherdatastorageandtransmissioncostcomparedtothedatacenter.Fewedgedevicesarelikelytohave
WHITEPAPER7
high-bandwidthnetworkconnections,constantconnectivityisnot
necessarilyagiven,andtransferringdatatoandfromthousandsofedgegatewaysisexpensive.Virtualmachineandcontainerimagesmagnify
thedatamovementcost,amountingtoclosetoacompletedistributiondownloadperapplication,duetoexistingpackaging.
Whilelayeredcontainerimagesareintendedtoreducethisoverhead,
third-partyapplicationpackagingmakesunderlyinglayerre-useunlikely.
Forexample,Armdevelopedaprototypehealthcareapplicationwith
machinelearning,whichused17Dockerimages,occupyingabout2.3GBofstorage.Deployingthisapplicationtothousandsofnodesovermeteredcellularnetworkingwouldnothavebeenpractical.Forthisreason,aswellasthesomewhatmoreconstrainedcomputecapability,wedonotseea
pure‘cloud-native’deploymenttoedgecomputingdevices,butrathera
frictionless‘cloud-like’modelwhichisaimedatdeliveringcloudbenefits,suchasportabilityandabstraction,inamorehardware-constrained
environment.
2.2Why‘CloudLike’inEdgeComputing?
FIG.3
BenefitsofCloudNative
Theefficienciesresultingfromminimizingtheoperationalburdenof
developers,administrators,andusersincloudcomputinghaveledtoothersegmentsevaluatingtheuseoftechnologiesoriginatingfromthecloudinotherenvironments.
WHITEPAPER8
Thedriverbehindthismovementisbasedonthelawofeconomics,namelythatthecloud-nativemodelofabstractionhasbeenshowntoaccelerate
timetomarketandsavecosts.Continuousdevelopment[
1
]isamajorcomponentofachievingafastertimetomarket.Theseadvantagesarerootedinseveralcorepropertiesofcloud-nativetechnologies:
—Portable,hardwareabstracted.
—Consistencyacrossanyinstallation/deployment.
—Timelyupdateswithoutcomplexre-integrationoverheads.
—Speedtimetomarketandmaximizere-use.—Fastapplicationdevelopmenttimes.
—Removeunnecessaryindustryfragmentationtoeliminatesiloedperplatformcosts.
2.3What’sChanginginEdgeComputing?
Digitaltransformationacrossindustriescontinuesatpace,bringingwithitnewinnovativebusinessservicesandnever-beforerealizedefficiencies.
FrombuildingthenextwaveofGigaFactoriestolow-carbon,energy-efficientcities,andtheelectrificationoftransport,acommonthemeunderliesitall—datainsightatascalenever-beforerealized.
Traditionalviewsofdatainsightarebuiltaroundadatacenter‘cloudcentric’model.Inthisscenario,sensordataissharedwiththecloud,inturnderivinginsightatscalethroughtechniquessuchasAI,todeliverthedesired
businessandefficiencyoutcomes.Thechallengecomeswithscaleandthesheernumberofconnecteddevices,andcorrespondingcomputedrives
theneedtoputprocessingclosetothesourceofthedata.Factorssuchaslatency,powerconsumption,cost,privacy,andconnectivity,alldrivethe
needtodeliverever-moresophisticatededgecomputing,ratherthansimplypushingdatatoremotecloud-basedserver.
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Aswellasfrictionlesscomputewhereitisneeded,otherfactorsare
requiredtomeetthescaleanddemandofedgeAIgrowthoverthenextfewdecades.
Scalingdatainsightandvalue:Simplyconnectingdevicestothe
cloudbringsneitherscale,noroperationalefficiency.Traditionalcloud
datacentersdelivergenericcomputeforusebybusiness-levelapplications.Conversely,edgedevicesformthe‘real-worldinterface’anddelivermassiveinsightatscaleintothosecloud-basedservicesplatforms.Howinsight
isenabledattheedgeandhowtheseconnecteddevicesaresecurelymanagedbecomesacriticalsuccessfactorinscalingnewapplicationsandservices.
Securityatscale:Thereisgrowingregulationaroundthemanagementofelectronicdataandproducts.TheEuropeanCyberResilienceAct,
theUKProductSecurityandTelecommunicationsInfrastructureAct
andtheEuropeanRenewableEnergyDirectiveareprimeexamples.
WithsimilarlegislationprogressingintheUS,theregulatorylandscapecouldposeariskoffinancialpenaltiesandlostreputationforthosewhofailtomanagethesecurityofdigitalhardwareandsoftwareadequatelyacrossdevicelifecycles.Trustthereforebecomesasignificantfactorin
enablingscale.Edgedevicesdonotbenefitfrombeinginatraditionaldatacentersettingandareinstalledwherevertheyareneeded.
Unliketraditionalenterprisedatacentermodelswhereserversaredeployedinsecurelocationswithhighlymanagedsecurity,inedgedeployments,
weseeverydifferentdeploymentandthreatmodels.Edgedevicesmust
bedeployedinawidevarietyoflocations,withhighlyvariablesecurity
threats,e.g.,publiclylocated,susceptibletophysicalattack,connectingviapublicnetworks,tonamejustafew.Establishingtherightlevelofsecurityandtrustforedgedevicesiscriticaltoscaleapplicationsandrealizethe
businessbenefits.
WHITEPAPER10
Operationalefficiency:Aswescaleoutedgecompute,operational
efficiencybecomesakeyconsiderationwhenconsideringtotalcostof
ownership.Wecanthinkaboutthisintwoways:Firstly,thedevelopmentcosttocreatetheapplicationorservice,andsecondly,theoperationalorrunningcostsoncetheserviceisdeployed.Sinceedgecomputedevicestypicallyhavealonglifetime(5to10years,orlonger)thetotalcostof
ownershipbecomesacriticalconsideration.Thecostsincurredtooperateadeviceincludefactorssuchaspowerconsumption(linkedtorunning
costsandcarbonefficiency),aswellasdevicemaintenancecosts
relatedtomanagingsoftwareupdatesandoverallproductlifecycle.Asthedeploymentofdevicesscalesandusecasecomplexitygrows,devicevendorsandserviceprovidersincreasinglylooktooptimize
operationalefficiency.
Agileinnovation:Ourtraditionalviewofcloudcomputeisbuiltaroundagiledevelopment.Thisdeliverstremendousefficiencybothinterms
ofcloudaccessibilitytoavastnumberofdevelopersviaconsistentand
hardwareabstracteddevelopmentflows,andanagilemindsetinproductdevelopment.Asusecasesbecomemorecomplex,developersare
lookingtoembracethebenefitsof‘cloud-like’innovationinedgeusecases.Examplesincludeabstractinghardwaredifferencesasmuchaspossible
andsupportinganagiledevelopmentflowthatfacilitatesrapidinnovation,fastvirtualprototypingandcontinuousdevelopmentandimprovement
(CI/CDflows).
2.4ChallengestoOvercome
Aswehaveseen,thedemandforedgecomputeisrelentless,butsotoo
istheneedforefficiencyatalllevelsifwearetorealizethevisionatscale.TraditionalIoT-connecteddevicesthatweseetodaygosomewaytosolvingthesechallenges,butastepchangeinhowedgedevicesareenabledmust
WHITEPAPER11
happenacrossallindustries.Wecansummarizethekeychallengesasfollows:
Developa‘cloud-like’mindsetattheedge:Thetraditionaldatacenter
modelof‘writeonceandrunanywhere’doesnotmapdirectlytoedge
devicesforpracticalreasons,howeverelementsofthatmodelarecriticalforaneffectiveedgecomputingevolution.Edgedevicestendtobe
applicationspecific(e.g.asmartcamera)butmustembraceelements
offrictionlessdevelopmentforspecificbenefits.Aswethinkaboutedgecomputingasanextensionofthedatacenter,weneedawholenew
mindsetintermsofhowaccessibletheseedgedevicesaretodevelopers,andhowtheysupportagiledevelopment,virtualprototyping,and
continuousimprovements.Todeliverthisvisionalsorequiresasignificantmindsetshiftfortraditionalembeddeddevelopers.Goneisthetraditional
‘linear’developmentflowofspecifying,implementing,testing,and
deployingapplications.Instead,weshifttoCI/CD/deliveryflowtospeed
timetomarket,maximizesoftwarere-useandultimatelyreducecost.
Todothis,themarketmustbuildcommonabstractedprogrammingmodelstoopentheaccessibilityofedgedevicestodevelopersacrossplatforms,
abstractingcomplexityandlimitinghardwaredependenciesexclusivelytowheretheseaddvalue,suchasforperformanceandpoweroptimization.
Securityandprivacyatscale:Abedrockofscalingthecloudouttothe
edgeisensuringrobustsecurityandprivacy.Buildingdevicesthathave
atrustedandconsistentapproachtosecurityiscriticalfortheirlifecycle
managementandensuringtrustaroundthedevice,connection,software
lifecycle,data,andservices.Withsoftwarestacksbecomingincreasingly
complexandmultivendor,weseegreateraneedforcomposablesoftware,wherebyeachpartyownsonlytheportionofsoftwarethattheycareabout.Withinthismodel,eachsoftwarecomponentessentiallyhasitsownsecurelifecycle.Underpinningthisistheneedforconsistentplatformsecurity
capabilities,suchassecureboot,secureupdates,securestorage,
WHITEPAPER12
andtrustedcrypto.Howeachofthesoftwarecomponentscanaccessthesesecureplatformservicestomanagetheirlifecycleiscritical.
Eliminateneedlessfragmentation:Needlessfragmentationholdsback
innovationandslowsthepaceofadoptionatscale.Itisthereforeessentialtoseekoutcommonalitythatremovesneedlessnon-differentiationsothesupplychaincanfocusonlyonthedifferentiationthataddsvaluetotheirbusinessandthemarket.Anobsessiveattentiontoefficiencyisneeded
bothinthedevelopmentofthedevice,aswellastheoperationalcosts.
Amodularapproachtosoftwaredeployment:Fragmentationchallenges
extendtosoftwareasweconsidertheincreasinglycomplexusecasesfor
edgedevices.Itiscommonplaceformultivendorsoftwarestackstorun
onanedgedevicewithmanythird-partycomponentsneedingtocome
togetherandinteroperate.Increasingly,end-marketdeploymentscareaboutwhatsoftwareisrunningonedgedevices.Fleetmanagers,forexample,
wanttoknowwhatoperatingsystemsaredeployed,whatsecuritypatchesarepushedout,andwheredifferentsoftwareassetsarecomingfrom.
Thedesireforchoice,coupledwithgrowingcomplexity,isdrivingtheneedformodular,interoperablesoftwarethatcanbemaintainedthroughoutitsdeployedlifetime.
Balancestandardizationanddifferentiation:Themarketmustembracestandardsandcommonalitywherenecessarytospeedtimetomarket,
reducetotalcostofownership,andeliminateneedlessfragmentation.
CollaboratingonArmcanbringtherightlevelofstandardization,while
allowinghardwareinnovationanddifferentiationtothrive.Thereisno
single‘recipe’foredgedevicesfromanArmplatformpointofview.
Instead,weconsider‘thesetofhardwareandsoftwareinterfacesneededtominimizethecostofbooting,running,andmaintainingoperatingsystemsandothersystemsoftwarethroughthelifetimeofthedevice’.
WHITEPAPER13
Benefitsofthisapproachinclude:
—Reducestime,cost,andeffortfromgettingsoftwaretoinstallandworkfordevicelifetimes.
—Removesnon-differentiatingcostfromtheecosystem.
—Allowstheecosystemtoinvestmoretimeandmoneyonworkthataddsvalue.
Today,initiativeslike
PARSEC
forstandardizedhardware-abstractedsecurityservicesarebecomingessential,asisaconsistentapproachtosecurity,whichisprovidedby
PSACertified
.Plus,through
ArmSystemReady,welookathowoperatingsystemsaresupportedonedgedevicesasacriticalfactor,alongsidetheneedtoofferandmaintainoperatingsystemdistributionsondevicesfortheircompletelifecycle,
whileeliminatingper-platformportingcosts.
HeterogeneityinedgeAI:Whenthinkingaboutcloudnative,
weimaginecontainerizedcomputeworkloadsthatcanruninafullyportablemannerinclouddatacenters.Asweestablishedearlyinthis
document,edgecomputingtendstobeapplicationspecificandoptimizedforcertainworkloadsandpower/performancebudgets.Overthelast
fewyears,weareseeingadeepeningtrendfor‘a(chǎn)cceleratedcompute,’wherebyhardwareaccelerationisappliedtocommonandcompute-intensiveworkloads.Acceleratedcomputetakesmanyformsbut
principallyfallsintotwoareas:
01In-lineaccelerationthatoccursaspartoftheCPUoperation(e.g.,ArmScalableMatrixExtensions).
02Offloadacceleration(e.g.hardwarethatsitsalongsidetheCPU,
suchasanNPU,bprovidingheterogeneityintheprogrammingmodel).
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Acceleratedcomputeisusedtoimproveperformance,reducepower
consumptionforspecificworkloads,orsometimesboth.Examininghow
developerexperiencesscaleacrossheterogeneousplatformsisessentialtoavoidneedlessfragmentationandsiloeddevelopmentsbecoming
deeplyentwinedtospecifichardwarevariants.Aswelooktowardsthe
evolutionofedgedevicesasoutlinedinthispaper,thepartialdecouplingofhardwareandapplicationasatrendmovesustowardan‘a(chǎn)pp-like’
modelthatfa
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