comparison of aws, azure, and oracle device modelsazure+oracle... · outline this presentaon takes...

ComparisonofAWS,Azure,andOracleDeviceModelsW3CWebofThingsOpenDay

26.3.2018,PragueMichael.Lagally@oracle.com

OutlineThispresentaJontakesafocusedviewonthedeviceconceptsintheIoTcloudplaNormsofAmazon(AWSDeviceShadows),MicrosoQ(AzureIoTHub)andOracle(IoTCloudService).Thedevicemodelforeachcloudserviceisstructuredinthefollowingway:•  HighLevelConcept•  DeviceDescripJon•  DeviceModel•  ProperJes•  AcJons•  Events•  SerializaJonformat•  CommunicaJonProtocols,MessagesandFormats,API,SecurityAcompleteoverviewofthesecloudplaNormsisbeyondthescopeofthispresentaJon–thestrikeoutsecJonsareintenJonallyleQout.

TerminologyThingorDevice

AphysicalorlogicalenJtythatismanagedbyanIoTCloudService

DeviceDescripJon(aka.ThingDescripJon)AserializedrepresentaJonofaDevice

DeviceModel(aka.DeviceTemplatesorThingTypes)Ablueprintthatdescribesthestructureandinterfaceofagroupofdevices

ProperJes,aka.AVributesorResourcesApartofthedevicethatcontainsstateinformaJonandmaychangeoverJme

Events(aka.MessagesorAlerts)

AnoJficaJonmechanismbetweentheDeviceandtheIoTCloudService

MICROSOFTAZUREIOTHUBDEVICETWINS

MicrosoQAzureIoTHub-DeviceTwinsReferences

•  ThefollowingisderivedfrompublicinformaJonavailableat:

•  hVps://docs.microsoQ.com/en-us/azure/iot-hub/iot-hub-node-node-getstarted

•  hVps://docs.microsoQ.com/en-us/azure/iot-hub/iot-hub-devguide-query-language

•  hVps://github.com/MicrosoQDocs/azure-docs/blob/master/arJcles/iot-hub/iot-hub-devguide-device-twins.md

MicrosoQAzureIoTHub-DeviceTwinsHighLevelSummary

•  MicrosoQ'sdevicetwinisanabstracJonofadevicestateusing(desiredandreported)properJesandasetoftags,containingmetadatavalues.

•  AcJonsandeventsarenotpartofthemodel,butarehandledbyapplicaJoncode.AcJonscancontainmulJpleparametersandtakeobjectsasparameters.

•  MessagesareratherlightweightandthecontentcanbeselectedbytheapplicaJondowntopropertylevel.TheformatofthemessagesisdefinedbyapplicaJonsonly.

•  Thedevicetwinmodeldoesnotdefinea"template"oramechanismtoaggregatemulJpledevicesintoacombineddevicemodel.

MicrosoQAzureIoTHubDeviceTwins

Source:MicrosoQ

Devicetwin•  AdevicetwinisaJSONdocumentthatincludes:•  Tags:AsecJonwherethesoluJonback-endhasaccessto.Theyarenotvisibletodeviceapps.

•  Proper<es:UsedtosynchronizedeviceconfiguraJonorcondiJons.

•  AllpropertyvaluescanbeofthefollowingJSONtypes:boolean,number,string,object.Arraysarenotallowed.

ProperJes3kindsofproperJes:•  Desiredproper<es:CanbesetbythesoluJonbackendandread

bythedeviceapp.TheappcanalsoreceivenoJficaJonsofchanges.

•  Reportedproper<es:ThedeviceappcansetreportedproperJes,andthesoluJonbackendcanreadandquerythem.

•  Deviceiden<typroper<es:TherootofthedevicetwinJSONdocumentcontainstheread-onlyproperJesfromthecorrespondingdeviceidenJtystoredintheidenJtyregistry.

AcJonsAcJonsdonotcorrespondtoaformaldescripJonintheJSONdocument,butaremodeledviaposJngofapayloadtoa"method"endpoint.AnacJoncantakeanarbitrarynumberofparameters.

EventsThereisnodedicatedeventmechanism.Eventscanbemodeledbyusingdevice-to-cloudmessages,whicharebeingsentunderapplicaJoncontrol.TheeventpayloadformatisnotspecifiedintheJSONdocument.

SerializaJonformat{"deviceId":"myDeviceId","etag":"AAAAAAAAAAc=","status":"enabled","statusUpdateTime":"0001-01-01T00:00:00","connecJonState":"Disconnected", "lastActivityTime": "0001-01-01T00:00:00","cloudToDeviceMessageCount":0,"authenJcaJonType":"sas","x509Thumbprint":{"primaryThumbprint":null,"secondaryThumbprint":null},"version":2,"tags":{"locaJon":{"region":"US","plant":"Redmond43"}},"properJes":{"desired":{"telemetryConfig":{"configId":"db00ebf5-eeeb-42be-86a1-458cccb69e57","sendFrequencyInSecs":300},"$metadata":{

...},"$version":4},"reported":{"connecJvity":{"type":"cellular"},"telemetryConfig":{"configId":"db00ebf5-eeeb-42be-86a1-458cccb69e57","sendFrequencyInSecs":300,"status":"Success"},"$metadata":{...},"$version":7}}}

AWSDEVICESHADOWS

References•  ThefollowingisderivedfrompublicinformaJonavailableat:

•  hVps://docs.aws.amazon.com/iot/latest/developerguide/what-is-aws-iot.html

•  hVps://docs.aws.amazon.com/iot/latest/developerguide/aws-iot-how-it-works.html

•  hVps://docs.aws.amazon.com/iot/latest/developerguide/iot-sdks.html

•  hVps://docs.aws.amazon.com/iot/latest/apireference/API_OperaJons.html

HighLevelConcept•  AWSIoTDeviceShadowsenableInternet-connected

devicestoconnecttotheAWSCloudandletapplicaJonsinthecloudinteractwithInternet-connecteddevices.

•  DevicesreporttheirstatebypublishingmessagesinJSONformatonMQTTtopics.EachMQTTtopichasahierarchicalnamethatidenJfiesthedevicewhosestateisbeingupdated.WhenamessageispublishedonanMQTTtopic,themessageissenttotheAWSIoTMQTTmessagebroker,whichisresponsibleforsendingallmessagespublishedonanMQTTtopictoallclientssubscribedtothattopic.

Thing–DeviceModelAWSIoTprovidesaregistrytomanagethings.AthingisarepresentaJonofaspecificdeviceorlogicalenJty:aphysicaldeviceorsensororalogicalenJtylikeaninstanceofanapplicaJon.InformaJonaboutathingisstoredintheregistryasJSONdata.Hereisanexamplething:{ "version": 3,"thingName":"MyLightBulb","defaultClientId":"MyLightBulb","thingTypeName":"LightBulb", "attributes": { "model": "123", "wattage": "75" }}

ThingsareidenJfiedbyaname.ThingscanhaveaVributes,whicharename-valuepairsthatcanbeusedtostoreinformaJonaboutthething,suchasitsserialnumberormanufacturer.

Thingtypes(Templates)ThingtypesThingtypesstoredescripJonandconfiguraJoninformaJonthatiscommonforallthingsassociatedwiththesamethingtype.Thissimplifiesthemanagementofallthings.ThinggroupsAllowtomanageseveralthingsatonce.Groupscanalsocontaingroups—youcanbuildahierarchyofgroups.

AVributes/Resources/ProperJes•  hVps://docs.aws.amazon.com/iot/latest/apireference/API_ThingAVribute.html

•  EachaVributevalueinJSONobjectscanhaveamaximumlengthof800bytes.

•  ThespecificaJonissilentaboutthesupportedaVributetypes,theexamplescontainonlysimpletypes.

•  HowevertherulesengineissupporJngallJSONtypesincludingarraysandobjects.

AcJons•  AcJonsdonotcorrespondtoaformaldescripJonintheJSONdocument,butaremodeledviaposJngofapayloadtoa"method"endpoint.

•  AnacJoncantakeanarbitrarynumberofparameters.

Events•  Thereisnodedicatedeventmechanism.Eventscanbemodeledbyusingdevice-to-cloudmessages,whicharesentunderapplicaJoncontrol.

•  TheyarenotpartoftheJSONdocument.

SerializaJonformat{"deviceId":"myDeviceId","etag":"AAAAAAAAAAc=","status":"enabled","statusUpdateTime":"0001-01-01T00:00:00","connectionState":"Disconnected","lastActivityTime":"0001-01-01T00:00:00","cloudToDeviceMessageCount":0,"authenticationType":"sas","x509Thumbprint":{"primaryThumbprint":null,"secondaryThumbprint":null},"version":2,"tags":{"location":{"region":"US","plant":"Redmond43"}},"properties":{"desired":{"telemetryConfig":{"configId":"db00ebf5-eeeb-42be-86a1-458cccb69e57","sendFrequencyInSecs":300},"$metadata":{

...},"$version":4},"reported":{"connectivity":{"type":"cellular"},"telemetryConfig":{"configId":"db00ebf5-eeeb-42be-86a1-458cccb69e57","sendFrequencyInSecs":300,"status":"Success"},"$metadata":{...},"$version":7}}}

ORACLEDEVICEMODEL

ReferencesThefollowingisderivedfrompublicinformaJonavailableat:•  hVps://docs.oracle.com/en/cloud/paas/iot-cloud/iotgs/toc.htm•  hVps://docs.oracle.com/en/cloud/paas/iot-cloud/iotrq/index.html•  hVp://www.oracle.com/technetwork/indexes/downloads/iot-client-

libraries-2705514.html •  hVps://docs.oracle.com/en/cloud/paas/iot-cloud/develop/developing-device-

soQware-using-client-soQware-libraries1.html•  hVp://www.oracle.com/webfolder/technetwork/tutorials/obe/cloud/iot/

IoT%20Quick%20Start%20JavaScript/IoTQuickStartJavaScript.html

HighLevelSummary•  TheOracleIoTCloudServiceplaNormmanagesdevicesandcorrespondingmessages

andevents.Atthecoreoftheserviceisthedevicemodel.•  Oracle’sdevicemodelisablueprintfordefiningdevices.Itcanbeusedtocreatedevice

instancesandsimulaJonswithouthavingaphysicaldeviceavailable.•  Thiscansignificantlyhelptovalidatethedevicemodel,beforeactuallybuildinga

device.•  SeparaJngtheblueprintfromthedeviceinstanceisusefultobuildaggregateddevices,

whichincorporatemulJpledevicemodels.•  Adeviceinstanceiscreatedbyregisteringadevice,whichimplementsoneormore

devicemodels,withtheIoTcloudservice.•  DevicemodelsanddevicedescripJonsaremanagedbytheIoTCloudService.Theycan

beexportedandimportedinaplainJSONformat,whichissimilartothe“WoTTD”format.

•  AsimpleWoT-TD-DMconverterisavailable.

DeviceModel•  Adevicemodelisacommonblueprint,thatcanbeappliedtomulJpledevices.

•  Itcontainsmetadata,aVributes,acJons,formatsandlinks.

•  DevicemodelsareuniquelyidenJfiablevia“urn”•  AdevicecanimplementmulJpledevicemodelssimultaneously.

AVributes•  AVributescanhavethefollowingtypes:number,integer,numberwithrange,integerwithrange,string,boolean,date&Jme,uri.

•  ComplexaVributes(arrays,objects)areintenJonallynotincluded,sincetheintegraJonwithexisJngback-endservices(e.g.AnalyJcs)requiressimpletypes.

•  AVributescanbereadonly.

AcJons•  AcJonsaretriggeredbysendingapayloadtothecorrespondingendpoint.

•  AcJonscancontainonlyasingleparameter.•  ThereasonforthisapparentlimitaJonistoenableverylightweightimplementaJons.

•  IfcomplexparameterswereneededtheycouldbeencapsulatedinaJSON-string.

Formats•  Formatsdefinethepayloadstructureformessages.

•  FormatsareuniquelyidenJfiablevia“urn”.•  Formatsareeitherregular“data”messagesor“alert”messagesthataresentunderapplicaJoncontrol.

•  Thepayloadofthealertmessageisdefinedinthe“formats”secJon.

DevicemodelserializaJonformat{"urn":"urn:com:oracle:iot:device:humidity_sensor","name":"HumiditySensor","description":"Devicemodelforsensorthatmeasureshumidity.","attributes":[{"name":"humidity","description":"Measureshumiditybetween0%and100%","type":"INTEGER","range":"0,100"},{"name":"maxThreshold","description":"Maximumhumiditythreshold","type":"INTEGER","range":"60,100","writable":true,"defaultValue":80}],"actions":[{"alias":"","description":"","name":“normalizeThreshold"}],

"formats":[{"urn":"urn:com:oracle:iot:device:humidity_sensor:too_humid","name":"tooHumidAlert","description":"Samplealertwhenhumidityreachesthemaximumhumiditythreshold","type":"ALERT","value":{"fields":[{"name":"humidity","type":"INTEGER","optional":false}]}}]}

TypicalIoTCSdeploymentscenarioIoT

CloudService

IoT

Gateway

DeviceModel

DeviceModel

MQTTDevice

CoAPDevice

Proprietaryprotocol(messages/alerts)

Apps Apps

OracleIoTClientLibrary

IoTServerRESTAPI

Apps Apps

Node-wotGateway

OracleIoT

CloudService

Node-wot+OracleIoTCloudServiceIntegraJon

DeviceModel

RESTAPI

OracleProtocol(REST/JSON)

IOTCSPlaNorm

Java/Weblogic Node.Js

ManualmappingorautomaJctranslaJon

GWexposesthings

Apps Apps

ThingDescripJon

OracleIoTClientLibrary

Gateway

Apps Apps

GWconsumesthings

3IntegraJonpointsGWconsumesdevicesexposedbyIoTCS(fromothervendors)-RequirestheGWtousetheRESTAPIoftheIoTcloudserviceIoTCSconsumesdevicesconnectedtonode-wotgateway-RequiresintegraJonoftheOracleIoTClientlibraryintotheGWMappingofthingdescrip<ontodevicemodel-  Thismappingcouldbedonemanuallyinthefirststep-  NoimplementaJoneffort

SUMMARY

Summary+Conclusion•  The3IoTserverplaNormssharemanycommonaliJesbetweentheir

devicemodels.Howevertherearesignificantdifferences.•  AWSandAzureonlydefineadatamodel,noacJonsandevents.•  NoneoftheserializaJonformatsareinterchangeable.•  Noneoftheformatsdefinesaprotocolbinding.•  Adevicemanufacturer,whowantstoaddresstheseplaNorms,hasto

createcodefor3differentenvironments.ThismayexceedthehardwarecapabiliJesonverysmalldevices.

AunifieddevicemodelwillsimplifytheintegraJontasksacrossdifferentplaNormsandwillaccelerateIoTmarketadopJon.