SimpleLink Wi-Fi® Enabled Electronic Smart Lock

1 1 SWAA169 December2017 SubmitDocumentationFeedbackCopyright 2017,TexasInstrumentsIncorporatedSimpleL ink Wi-Fi EnabledElectronicSmartLockApplicationRep ortSWAA169 December2017 SimpleLink Wi-Fi EnabledElectronicSmartLockBenjaminMoore, SimpleLinkWi-FiApplicationsTeamABSTRACTT hisapplicationreportdescribesthe developmentof Wi-Fi enabledelectronicsmartlocks(e- locks ).Spe cifically,the benefitsof addingWi-Fito an e-lockdesignare casesare presentedalongwith an estimateof systembatterylife for two SimpleLink Wi-Fimakesit possibleto createa batterypowerede-lockdesignthat can be securelymonitoredand controlledfromthe SmartLockReferenceDesignEnabling5+ YearsBatteryLife on 4 AA Batteries[1] is referencedthroughoutthis documentas theSmartLockReferenceDesign.

2 For a list of supportingdocumentationand additionalresources,see (E- locks ).. Casesand Lockis or PowerUse of CC3220 SFromHibernateto TLS Connectionto CC3220 SFromHibernateto TLS Connectionto CurrentWithLSI = 500 SimpleLink of December2017 SubmitDocumentationFeedbackCopyright 2017,TexasInstrumentsIncorporatedSimpleL ink Wi-Fi EnabledElectronicSmartLockTrademarksSimp leLink,MSP430,CapTIvate,Internet-on-achi p,TexasInstruments,LaunchPad,BoosterPack ,MSP432are trademarksof a registeredtrademarkof a trademarkof a registeredtrademarkof othertrademarksare the propertyof December2017 SubmitDocumentationFeedbackCopyright 2017.

3 TexasInstrumentsIncorporatedSimpleLink Wi-Fi EnabledElectronicSmartLock1 IntroductionThoughtraditionallockshavebe enaroundfor thousandsof years,doorlockshavecontinuouslyevolvedin to morecomplexsystemswith integratedelectroniccontrolsand accesshomesand buildings,whileactingas the first line of defensein locksare commonlycalledelectronicsmartlocks(e-loc ks).E-locksare changingthe way wethinkaboutand interactwith ,fobs,pin numbers,or evenmobiledevicescan act askeysthat lock or unlocka manyresidentialapplications,e-lockscan eliminatethe needfor usersto ,changingthe formof the key usedto opena doorhelpsaddressoneof the mainproblemsfacedby traditionallocks providinga methodfor quicklycreatingand an e-locksystemmakesit easyto createand manageaccesskeysat enablesnew features,suchas the abilityto remotelymonitorand.

4 IntegratingWi-Fidirectlyinto the e-lockeliminatesthe needto use a bridgeforconnectingthe lock to the integrateddesignprovidesan all-in-oneproductthat reducesoverallBOMcost and enablesapplicationsthat demandhigh throughputdirectlyto the casesfor and benefitsof integratingWi-Fiin an electronicsmartlockdesign,as well as someof the key requirementsfor e-lockswith ,this guidedescribeshow SimpleLinkWi-Fienablesthe developmentof batterypowerede-locksthat can be securelymonitoredand controlledthroughthe followingterminologyis usedthroughoutthis Asymmetrickey pairsare usedin algorithmswhereone partyperformsacryptographicoperationwith a key that is not the sameas the key usedto applythe pairsare definedas publicand privatekeys,and usedmostlyfor digitalsigningandsymmetrickey Authenticityensuresthat assetsor entitiesare genuineand authorizedto performa taskor usedas verificationprocessusuallyinvolvescrypto graphicalgorithms.

5 Whichcheckthat the entitiesare who they claimto be. Somepredefinedtrustmechanismis alwayspart ofan Certificatesare publickey of thesubject,and a CA signatureof the headerand publickey. Anyoneprovidedwith the CA publickey(or sub-CAin caseof certificatechain)can verifythe subject s Confidentialityensuresthat an assetis not madeavailableor mostcases,confidentialitytranslatesinto encryption,whilein othercases,obfuscationtechniquesare usedto Integrityis an attributedescribingan objectthat remainsintact,in its entirety,comparedto Keysare usedfor dataencryption,key establishment,and key lengthsand typesdependon the algorithmused,theirpurpose,and the Measuresthat aim to providethe intendedprotectionof (E- locks )

6 December2017 SubmitDocumentationFeedbackCopyright 2017,TexasInstrumentsIncorporatedSimpleL ink Wi-Fi EnabledElectronicSmartLock3 ElectronicSmartLocks(E- locks )E-lockscan typicallybe classifiedin two categoriesbasedon wherethey will be used: Commerciallocks(hotel,office,shoppingcen ter,and so on) Residentiallocks(homeor apartment)Systemdesignconsiderationsare impactedbasedon whethera lock will be usedto securea residentialbuildingor a designedto be usedon the exteriorof a houseand are typicallylocatedon the residentialuse typicallyoperateon batterypowerand are expectedto last aleastone yearbeforethe batteriesmustbe distancebetweenthe doorand the in-homeroutercan vary,it is necessaryto choosea Wi-Fidevicewith robustconnectivityfor technologiesare typicallyusedto supportthe peer-to-peerconnectionbetweena key (fob or mobiledevice)

7 And a showsa diagramof the typicalwirelesslinksin a be placedon the exteriorof a buildingto preventinitialentryand on the interiorofthe buildingto controlaccessto areasrestrictedfor use by be line-powered,but manyoperateon ,commerciallocksface strictpowerconstraintsbecausethey are oftendeployedin largenumberof batterypoweredlocksacrossa buildingleadsto a largeamountof maintenanceeffortand cost whenbatteriesmustbe ,Wi-Fisolutionswith extremelylow-powermodesand fast wake-uptimesareessentialto Casesand Benefits5 SWAA169 December2017 SubmitDocumentationFeedbackCopyright 2017,TexasInstrumentsIncorporatedSimpleL ink Wi-Fi EnabledElectronicSmartLock4Wi-FiUse Casesand BenefitsIntegratingWi-Fiinto an electronicsmartlock designprovidesclearadvantagesoverotherlo w-powerRFtechnologiesthat do not providea directconnectionto the directWi-Ficonnectionto a homeaccesspoint(AP)makesit possibleto.

8 Lockor unlockthe doorfromanywhereinternetconnectivityis available Knoweverytime the dooris lockedor unlocked Performfast Over-the-Air(OTA)updatesfromanywhere Easilyadd or removeauthorizedusersand authenticatethroughthe cloud Reducesystemcost and improveend-customereaseof use with a singledoor-locksolutionconnecteddirectly to the UnlockFromAnywhereConnectingan electronicdoorlock directlyto yourhomeaccessAP makesit possibleto accessthe lockfromanywherethroughthe lock connectsto the AP, the lock can createa connectionwith a usercan thencommunicateto the lock throughthe cloudserverwithanotherinternet-connected devicesuchas a smartphone,tablet.

9 Or cloudconnectivityby alwaysknowingwhetherthe lock is openor the lockis accidentallyleft open,a usercan quicklycheckthe statusof the lock and thensecureit fromthe mobiledevicewithouthavingto ,a homeownerwith remotecontrolof a lock can choosetolet someoneinto theirhouseat any especiallybeneficialif someonelosestheirkey or doesnot needpermanentaccessto the home(for example:repairman,postalworker,and so on). Lockis AccessedAnotherbenefitof integratingWi-Fiinto an electronicsmartlock is that a usercan get a notificationanytime the lock is stateof the lock is changed,the lock can publishthat informationtothe cloudserver,whichcan thenforwarda notificationmessageon to the ,the ownerof the lock has the convenienceof knowingwhensomeoneis at example,a notificationcan be generatedwhenchildrenget backfromschoolor whenahousekeeperarrivesto cleanthe ,a notificationcan be sent to the ownerif someoneattemptsto tamperwith the lock or breakinto the internet-connectedproductslike Wi-Fienablede- locks .

10 It is necessaryto havea methodfor updatingthe systemfiles and files that mustbe replacedovertime are devicecertificatesand keysthat are usedby the cloudto identifyand establishsecureconnectionsto the also be requiredto enablenew features,fix existingissues,or typicallyinstalledin doors,it is impracticalfor a userto removethe lock fromthe doorand use a physicalconnectionto performthe wirelessupdatemechanism,knownas an over-the-air(OTA)update,providesa simpleway to keepthe implementedwith otherlow-powerRF technologies,but theseare example,usinga low-powerpeer-to-peertechnologyrequiresa userto be physicallypresentto enablethe this case,the updateis delivereddirectlyfromthe user'smobiledevicetothe lock usinga ,dependingon the throughputprovidedby the technology,a usermay haveto wait severalminutesfor the updateto.