IntroductionAtPlugableweloveconnectingthings.OurUSBproductsdothatwithreliablewiredconnectionsandwewanttoprovideyouwithproductsthatdothesameforyourBluetoothwirelessdevices.Wewanttohelpconnectyoursmartphone,computerandalloftheInternetofThings(IoT)goodiescomingtothemarketplace.AllofusknowBluetooth;ithasbeenaroundforwelloveradecade.AsSheldonCoopersays,“EverythingisbetterwithBluetooth!”1.Butmostofusknowthetechnologyprimarilyforitsroleasanaudioconnectionbetweensmartphonesandheadsets.Itismuchmoreandnowhastwodistinct‘flavors’tomeetmarketneedsrangingfromaudiotoIoT.Inthisarticle,we’llgiveabitofbackgroundinwirelessandBluetoothtechnology,andthendiscussthenewerBluetoothLowEnergyversion(alsocalledBluetoothSmart)ofthestandard.

Wirelessoverview

WirelesstechnologyWiredconnectionsarefantasticbecausetheycantransferdataandpoweratthesametime.Butourdevicesaremobilesothatwecaninteractwiththemwheneverandwhereverwewant,anditjustdoesn’tmakesensetoconnectcablesallofthetime.Alltechnologieshavetheirtradeoffs;wirelesstechnologieshavethreemajorfactorsthatinteract:speed,powerandrange.Itturnsoutthatlikealotofthingsinlife,youcan’thavethebestofallthree.Wejustcan’tgetaroundphysics;italwayswins.Thechartbelowsubjectivelyillustratesthetradeoffsbetweenseveralcommerciallyavailablewirelesstechnologies.

1TheBigBangTheory:https://www.youtube.com/watch?v=H_lf8_pxg2Q

Interactiveview:https://plot.ly/~billsalt/4/wireless-technology-attributes/

AtPlugable,wefocusonshort-rangetechnologiesthatdon’thaveradardishesorbillingplans.Weprovidegearthatworkswithinyourhouseorbusinessandcaneasilyconnectdevicesthathavethelongerrangeandcloudconnections.Whilethereseemtobeseveralchoicesvyingtobetheshort-rangewirelesstechnologythatenablestheIoTandmobiledevices,rightnowWiFi®andBluetootharetheclearchoicesformobileproducts.EveryhandsetandoperatingsystemtodaysupportsWiFiandBluetooth,andbothwirelesstechnologiescontinuetoimproveandproliferate.

Bluetoothvs.WiFiWhydoweneedbothBluetoothandWifi?Theyservetwodifferentpurposes,andbecauseofphysicswecan’thaveeverythingwewantwithjustone.WiFiisdesignedforhigh-speedlarge-scalenetworkandinternetconnectivityforrelativelystationaryusage:inoneplace.Thisincludesconnectingyourlaptopatworkandyoursmartphoneatthecoffeeshop,airportorhotel.Inthesecasesyouwantgreatspeedwhileyouareinthatparticularareaandusuallyhaveaplacetopluginyourdeviceifyouwanttoconnectforalongertime.Bluetoothisdesignedforconnectionstobattery-poweredthingsaroundapersonaldevice:inamobileenvironment.Inthisenvironmentweneedatechnologythatsupportsdevicesrunningonbatteriesandwithoutneedingtoplugtheminandrechargefrequently.Thedevicesareusedinplacesthatwiredinfrastructureisprohibitiveduetocost,powerandmobility.Familiarexamplesincludetheheadset

connectedtoyoursmartphone,connectionstoyourcar,andportablespeakersonthebeach.Alongwiththetrade-offsdescribedaboveinpower,rangeandspeed,thesetechnologiesalsohavedifferentcostandsizefactorsthatgiveBluetootharealadvantagefordevicesthatneedtobebothverylowcostandpoweredbysmallerbatteries.Bluetoothtechnologywasspecificallydesignedtosupportreal-timeaudioasanativestandarddatastream,whileWiFirequirestheadditionalVoiceoverIP(VoIP)protocolsincludingseveralproprietaryimplementations.WiFialsorequiresadditionalinfrastructurethatconsumesevenmorepowerwithhigherdataraterequirements.Inadditiontoaudio,Bluetoothtechnologyalsosupportsmedium-speeddatatransfersofserialandIPdatathatisusedinpoint-of-saleprintersaswellasotherapplicationsinconsumer,industrial,andmedicalproducts.ThechartbelowsubjectivelyillustratesthisandalsoincludesBluetoothLowEnergy(moreonthatlater).

Bluetooth LE

Bluetooth Classic

WiFi 802.11 2.4GHz/5GHz

Cost 4 8 "9/4"

Power 4 8 "9/4"

Size 4 8 9

Voice ✗ ✔ ✔

Speed 4 0 "8/4"

Typical Range 0 8 "4/8"

Worse ç è Better

4 9 0 8 4

BriefBluetoothhistoryBluetooth2wirelesstechnologyformallybeganinameetingproposedbyEricssonMobileCommunicationsin1998followingtheirownworkanddiscussionswithIntelandincludedtheotherfoundingmembers:Nokia,IBMandToshiba.ItwasdesignedtobeanopenstandardintheunlicensedIndustrial,ScientificandMedical(ISM)radiofrequencybandat2.4GHzandabove.Thegroupsetouttodevelopawirelessconnectiontechnologytoprovideforcommunicationsbetweenmobilephonesandperipheraldevicesforshort-term(ad-hoc)connectionsandinitiallyreplaceserial(RS-232)cables.AcompanywascreatedtoholdthepatentsandprovideforspecificationdevelopmentandtestingcalledtheBluetoothSpecialInterestGroup(SIG)3.Thisgrouphastheresponsibilityforprovidingapprovals,promoting,anddevelopingthespecification.SincetheintroductionofBluetoothLowEnergy,theoriginaltechnologyisnowalsocalled“BluetoothBR/EDR”whichreferencesitsBasicRate/EnhancedDataRatefeatures.Belowisabriefhistorywithhighpointsoftheevolutionofthetechnology:

• Bluetooth1.1(2001)o Firstpracticalspecificationo Fixederrorsinoriginalspecificationthatmadeitrelativelyunusableo AddedRSSI(ReceivedSignalStrengthIndication)o RatifiedasIEEE802.15.1(2002)

• Bluetooth1.2(2003)o AdaptiveFrequencyHopping(AFH)greatlyimprovesco-existencewithWLANo Improvedvoicequalityo Improveddatarateso RatifiedasIEEE802.15.1-2005

• Bluetooth2.0(2004)o Erratao EnhancedDataRate(EDR)–3xspeed

• Bluetooth2.1(2007)o QualityofService(QoS)o SecureSimplePairing(SSP)o SecurityImprovements

• Bluetooth3.0(2009)o BluetoothHighSpeed:AlternateMAC/PHYo Notwidelyimplemented…

2ThetechnologyisnamedafterKingHaraldBlåtandofDenmarkfromabout940untilabout986.KingHaraldwasnicknamedBluetooth,withatleasttwopossibleorigins:helovedandatelotsofblueberriesthatstainedhisteeth,or(morelikely)hefoughtalotandhad‘dead’frontteeththatlookedabitblue.3Seewww.bluetooth.com

WhatwasBluetoothmissing?Bluetoothgotofftoagoodstartandfoundits‘killer’marketintheaudioconnectionswithheadsetsandcars.Initialthoughtswerethatthesupporteddataprofilesandprotocolsweren’tquiterightforapplicationsthatneededahigherdata-rateconnectionandchallengedWiFi,butthoseneverseemedtobeagoodfitforBluetooth,evenwiththeincreaseddataratesofthe2.0and3.0specifications.4WhileBluetoothwasandisusedinmanysensorandremoteapplications,itdoesn’tprovidetheabilitytoworkinlowdatarateapplicationsrequiringsmallbatteriesandextended(foryears)operationwithoutchargingbatteries.AnewtechnologycalledWiBreewasintroducedbyNokiain2006thatleveragedmanyaspectsofBluetoothtechnologyandhadagreatlysimplifieddesign.ItallowedforthelowerpoweroperationinlowdatarateapplicationsthatBluetoothwasmissing.Afterseveralyearsofdiscussionandseveralkeychangestomakeitmorecompatiblewiththeexistingspecificationandtechnology,theBluetoothSIGformallyadoptedthisinversion4.0asafeaturecalled“BluetoothLowEnergy.”Ithassincebeenformallynamed“BluetoothSmart”formarketingpurposes(thoughrumorhasitthatitwillbechangingbackto“BluetoothLowEnergy”or“BluetoothLE).BluetoothBR/EDRandBluetoothLEdevicescannotdirectlyconnectwitheachothersincetherearefundamentaldifferencesbetweenthem.ThisissuehasbeenminimizedbyoneofthekeyfeaturesofBluetoothLEthathasallowedforitseaseofimplementationandwideproliferation:ThelowenergyversionisdesignedtoallowimplementationinintegratedcircuitswithrelativelysmallchangesfromtheirBluetoothBR/EDRdesigns.ICmanufacturershavequicklyimplementeddual-modechipsallowingcomputer,smartphoneandtabletmanufacturerstoaddBluetoothSmartcapabilityatalmostnoextracost.Thesedual-modedevicesarelabeledasBluetoothSmartReady(meaningthattheycantalktobothtypesofBluetoothdevices).AfurtherbitofconfusionisthattheBluetooth4.xspecificationsandapprovalsincludebothtypesandsodevicesqualifiedforBluetooth4canimplementeitherBR/EDR,LowEnergy(Smart),orboth(SmartReady).AbriefhistoryoftheBluetoothlowenergydevelopment:

• Bluetooth4.0(2011)o AddednewBluetoothlowenergy(BluetoothSmart)o Providedfordual-modeimplementations(SmartReady)

• Bluetooth4.1(2013)o Multiple-role(Central/Peripheral,Master/Slave)devices

4Alternativeimplementationsdescribedin3.0includedBluetoothover802.11(WiFi)thatwasprototyped,butneverwidelyutilized.The3.0revisionalsoproposedaveryhighspeedtransportinconjunctionwiththeUltra-Wideband(UWB)groupthatnevermaterialized.

o IoTarchitecturalenablerso Addedhand-offbetweenBR/EDRandLowEnergydevices

• Bluetooth4.2(2014)o IoT,IPV6enablerso Increasedpayloadperconnectioninterval(higherdatarate)o ImprovedBluetoothlowenergysecuritytomatchBluetoothBR/EDR

BluetoothBR/EDRoverviewLet’stakeaquickoverviewofBluetoothBR/EDRtogivesomecontextforourmaindiscussionofBluetoothLowEnergy.BluetoothBR/EDRtechnologyutilizesafrequencyhopping,spreadspectrum(FHSS)radioatupto20dBM(100mW)ofpowerthatallowsoperationuptoabout100meters.5Devicescanimplementdifferingpoweroutputandreceivesensitivity,so‘yourmileagemayvary’.AllPlugabledevicesaregoodforatleast10meters.BluetoothBR/EDRdividesradiobandwidthinto79channels,each1MHzwideandhopsinapseudo-randomsequencebetweenthemat1600timespersecond.Allthedatapacketsareerrorcheckedandprovidevaryinglevelsoferrorcorrection,sothatlostordamagedpacketsarecorrectedorautomaticallyretransmitted.Sincetheradiohopssoquickly,anylostordamageddatapacketsareretransmittedonadifferentchannel(frequency),providingagreatdealoftoleranceofradiointerferenceandmakingBluetoothaveryrobustconnection.

DevicesareeitherMasterorSlaves(orinsomecasesboth)andareconnectedinastarconfiguration.Onemastercanconnectwithupto7slavessimultaneouslyfordataconnectionsoramaximumof3audioconnections,oracombinationofbothasthebandwidthallows.Maximumrawdataratesare1mbpsforBasicRate(BR)or3mbpsforEnhancedDataRate(EDR).Realizablethroughputfordataisroughly75%(higherforaudio5Lotsofpeoplestillremembertheoriginal10mW,10dBMpowergiving10meters,andsomethinkthatwas10feet(Americans!).TherealityisthateventhelowpowerBR/EDRBluetoothdevicesoftenexceedthis.ItisalsoimportanttorememberthatrangedependsonbothdevicessinceBluetoothisalwaysa2-wayconnection.

sinceitallowsdroppedpackets),butalsodependsheavilyonthehardwareandsoftwareimplementations.

PairingandsecurityThedevicethatwantstobethemasterstartsoutbyperformingadiscoverytofinddevicesthatareadvertisingforaconnection.Devicescansimplyconnectusingoneofseveralmethods.Historically,deviceswereconnectedsecurelybytheexchangeofafixed4-digitPIN(headsetsusedtouse0000,forexample).Muchbetterandmoresecureimplementationshavelargelyreplacedthatmethod(althoughalotofpreviouslydesigneddevicesarestillshippingwithfixedPINsecurity).Thecurrentsecurityimplementationuses“SecureSimplePairing”(introducedinBluetooth2.1)allowingseveralmethodsforsettingupasecureconnection.Theappropriatemethoddependsonthecapabilitiesofeachdevice(display,keyboard,etc.).Theseareshownbelow:

• Justworks:Asthenameimplies,thismethodjustworks,withnouserinteraction.However,adevicemayprompttheusertoconfirmthepairingprocess.Thismethodistypicallyusedbydevicessuchasheadsetswithverylimitedcapabilities,andismoresecurethanthefixedPINmechanismthislimitedsetofdevicesusesforlegacypairing.Thismethodprovidesnoman-in-the-middle(MITM)protection.

• Numericcomparison:Ifbothdeviceshaveadisplay,andatleastonecanacceptyes/nouserinput,theymayuseNumericComparison.Thismethoddisplaysa6-digitnumericcodeoneachdevice.Theusercomparesthenumberstoensuretheyareidentical.Ifthecomparisonsucceeds,theuserconfirmspairingonthedevice(s)thatcanacceptaninput.ThismethodprovidesMITMprotection,assumingtheuserconfirmsonbothdevicesandactuallyperformsthecomparisonproperly.

• PasskeyEntry:Thismethodmaybeusedbetweenadevicewithadisplayandadevicewithnumerickeypadentry(suchasakeyboard),ortwodeviceswithnumerickeypadentry.Inthefirstcase,thedisplayisusedtoshowa6-digitnumericcodetotheuser,whothenentersthecodeonthekeypad.Inthesecondcase,theuserofeachdeviceentersthesame6-digitnumber.BothofthesecasesprovideMITMprotection.

• Outofband(OOB):Thismethodusesanexternalmeansofcommunication,suchasNearFieldCommunication(NFC)toexchangesomeinformationusedinthepairingprocess.PairingiscompletedusingtheBluetoothradio,butrequiresinformationfromtheOOBmechanism.ThisprovidesonlythelevelofMITMprotectionthatispresentintheOOBmechanism.

ProfilesBluetoothBR/EDRconnectionsdependonprofiles.Aprofileisacollectionoffeaturesandprotocolsthatimplementaparticulartypeofconnection.Forexample,theHeadsetprofileallowsaphonetoconnectandtransferreal-timeaudiodata

whiletheSerialPortProfile(SPP)allowsforadataconnectionsimulatinganRS-232cablebetweentwodevices.BluetoothBR/EDRrequiresoperatingsystemimplementationforeachprofilesupportedbyadevice.Thismeansthatdevicesarelimitedtopublishedprofilesandconstrainedbytheonesthatareimplemented;itisnotpossibletoaddnewBluetoothBR/EDRprofileswithoutacompleteupdate.Ashortexcerpted(notcomplete)listofcommonlyusedprofilesisshownbelow:

• GenericAccessProfile(GAP)–theoneprofilerequiredofalldevices,itsupportsqueriesofdevicetypeandfunctionandsupportsidentificationandsettingupadditionalprofiles

• SerialPort–functionsrequiredandmethodsforestablishingavirtualserialconnectionbetweentwodevices;itisusedinmanyofthehigherlevelprofiles

• Dial-upNetworking–functionsandmethodsrequiredtoestablisharemoteinternetconnection

• Handsfree–functionalitytoimplementahands-freeheadsetforcellphonesandcomputers

• AdvancedAudioDistributionProfile(A2DP)–functionalityforstereoheadsetsandplayersintendedformusicplayback

• HumanInterfaceDevice(HID)–functionalitytosupportkeyboard,mouse,joystick

• FileTransferProfile(FTP)–functionstosupporttransferoffiles• ObjectPushProfile(OPP)–anotherprofiletofacilitatetransferoffiles

BluetoothLowEnergyBluetoothLowEnergyis“notyourfather’sBluetooth”.Whilejustasrobust,itconsumesmuchlesspowerandcanbeimplementedatlowercost.Thetablebelowcomparesthetwo;severalofthesefeatureswillbediscussedbelow.

FeatureBluetoothBR/EDR BluetoothLE Notes

PowerAAAbatteriesforhours/days

Coincellsformonths/years

Lowerdatarate,moreefficientconnections,fewer/widerchannels

DatathroughputBR720kbpsEDR2200kbps

4.x:125kpbs4.2:300kbps

Thesearetypical,realizablethroughputfigures.Mileagewillvarywithimplementation.

Connections 7 ThousandsLowEnergyislimitedbyimplementation,notspecification

Packettypes 28 3 MandatoryplusoptionalProtocols 9 1

FrequencyChannels 79 40

Channelwidth 1MHz 2MHzAdvertising allchannels 3dedicatedAdaptiveHopping Yes Yes Samerobustcoexistencemethod

Oneofthebasicdifferences,andonethatshowsimmediatelywhythetwokindsofBluetoothcannot‘talk’witheachother,isshownbythefrequencydiagrambelow.WediscussedthatBluetoothBR/EDRhas79channels,butshownbelowarethefewer,widerchannelsusedbyBluetoothLowEnergy.

NotethatforBluetoothLowEnergy,threeofthechannelsaredesignatedfordedicatedadvertisingandaredesignedaroundWiFichannels1,6and11.TheBluetoothBR/EDRmethodisforadevicetohopinadifferentsequenceatamorerapidpaceandlookforadvertisers.Hoppingrapidlyhelpstoincreasetheoddsintherandomprocessofhoppingtothesamechanneltoconnect.TheuseofdedicatedadvertisingchannelsallowsBluetoothLowEnergytoconnectmuchmorequicklyandtofurtherreducepowerconsumption.

CreatingconnectionsBothBluetoothBR/EDRandLowEnergyusetheconceptofprofiles.BluetoothLowEnergybothsimplifiesandextendsprofiles,andallowsforthecreationanduseofcustomprofiles,somethingnotsupportedorallowedforinBluetoothBR/EDR.ProfileshavebeenpreviouslydiscussedforBluetoothBR/EDR.BluetoothLowEnergyonlyhastworequiredprofiles:GenericAccessProfile(GAP,similartoBluetoothBR/EDR)andGenericATTributeprofile(GATT).AllotherprofilesforBluetoothLowEnergyarebasedonGATT,sooperatingsystemsonlyneedtosupportGATTtoallowforahugerangeofstandardandcustomerprofiles.Atypicalsoftwareimplementationisshownintheblockdiagrambelow.

GAPdefinesthetworolesofCentralandPeripheral,andthetwoactivitiesofScannerandAdvertiser(respectively).GAPisusedtocreatetheconnectionandisalsoresponsibleforsecurity,pairingandbonding.TheconnectionprocessimplementedbyGAPisshownbelow.

BluetoothLowEnergyusesonlytheSecureSimplePairingdiscussedforBluetoothBR/EDRaboveforauthenticationaswellasestablishingthekeysforencryptionandbonding.Theterms‘bonding’and‘pairing’areoftenusedinterchangeably,buttheyarenot:Pairingistheactivityofauthenticatingandexchangingkeysthatareonlygoodforthecurrentconnection6.TosummarizetheconnectionprocessforBluetoothLowEnergy:

� Deviceswithservices(seebelow)advertise(GAP)� Usesselectedadvertisingchannelstospeeddiscovery

� Deviceswantingtousethoseservicesscan(GAP)� Collectadvertisingpackets� (Optionally)askforextendedscanpackets� Requestconnection� Pair(temporary)� Bond(optionally)� Setupconnectionparameters

� Readservices,read/writecharacteristics,acceptnotifications(GATT)� …� Disconnect

ServicesandProfilesGATTdefinesjusttworoles:ClientandServer.Onerequestsdataandtheothersuppliesit.TheCentralistheScannerandusuallybecomestheclient,butthatrolecanbereversed.UsuallytheAdvertiseristhePeripheralandbecomestheServerofdata.BluetoothLowEnergyextendstheprofileconceptbyintroducingservices.Aserviceimplementsoneormorefeaturesandcanbeusedasbuildingblocksforprofiles.SinceservicesarebasedonGATT,customservicescanbecreatedandusedwithproductsthatmaynothaveanybuilt-insupportforthem.Profilesupportcanbe(andoftenis)includedintheapplicationsoftware,suchasanapponasmartphone.Examplesofservicesare:

• Batteryservice–reportsthestateofchargeofthebattery• DeviceIDservice–reportsinformationaboutadevicesuchasthe

manufacturer,revisions,etc.• Heartrateservice–reportsthecurrentheartratemeasurement

Aprofilecancontainoneormoreservicesandtheconceptencouragesre-useofservices.Forexample,ahoverboard7profilemightinclude:

6Ifdevicesrequesttokeepthatinformationforfutureconnections,thekeysarestoredtospeeduptheprocessbybonding.Thusbondingrepresentsstoredpairinginformation.7Plugabledoesnotendorseorcondonetheuseofhoverboards.Wejustthinkthey’recoollookingandmakeagoodexamplehere.

• Batteryservice-standard• DeviceIDservice-standard• Hoverboardservice–custom.Reportsspeed,turnson/offlightsandsets

limitsfor‘catchfire’time8.Therelationshipofservicesandprofilesisshowninthediagrambelow9:

GATTGATThandlestheexchangeofdataforBluetoothLowEnergy.TheGATTserverstoresthedataandacceptsAttributeProtocolrequests,commands,andconfirmationsfromtheGATTclient.TheCharacteristicisthebasicbuildingblockfordataexchangedefinedbyGATT,andServicesaredefinedasasetofCharacteristics.Initssimplestform,aCharacteristicisacollectionofbytesandproperties.Characteristicscanbereadandwritten.Inaddition,aCharacteristic’spropertiescanbesetsothatitwillnotifytheclientuponeventssuchasachangeinvalue.Thesenotificationsareasynchronoussothattheclientdoesnotneedtopollforchanges,whichallowsfurtherpowersavings.8Justkidding.9FurtherinformationonProfilesandServicesforbothBR/EDRandLowEnergy:https://developer.bluetooth.org/TechnologyOverview/Pages/Profiles.aspx

ServicesmaycontainacollectionofCharacteristics.Characteristicscontainasingle(ormulti-byte)valueandanynumberofdescriptorsdescribingtheCharacteristicvalue.

Moreonadvertising:UndirectedadvertisingandbeaconsBluetoothLowEnergyadvertisingisquitedifferentfromBR/EDR.Advertisementscomewithapayloadofdata.Thisdatacanbeusedtodescribethedevice,itsname,availableservices,orsimplysentasdata.AdvertisementscanoptionallybemarkedasdirectedtowardsaparticularScannersothataScannercanfilterresponsesandfurtherspeeduptheconnectionprocess.Normaladvertisementsareundirectedandmayevenbemadebydevicesthatdonotevenacceptaconnection.Thinkofthisasabroadcastorasitisoftencalled,a“beacon.”Abeaconcantransmit31bytesofdata,andaScannercanrequestanextendedscanofanother31bytesfromdevicesthatsupportit.ApplehasusedthistoformtheiBeaconspecificationthatworkswiththeirOS,andothershaveproposedandimplementedalternativeformats10.Beaconshavegreatpotentialforuseinretail,factory,andhomesettings.TheycanbeusedalongwiththeProximityservicetolocatepeople,places,andthings.Standardsandusemodelsarestillevolving,butthismaywellbeanotherkillerapplicationforBluetooth(LowEnergy).

BluetoothlowenergyfutureThefutureofBluetoothisverybright.TheSIGhasannounceditsroadmapforthenextyear11anditisclearlyworkingtowardsfillinggapsandpushingthetechnologyforwardtomeettheneedsoftheIoTandkeepitcompetitivewithotheravailabletechnologies.Thehighlightsoftheneartermare:

• ImprovingIoTsupportwithextensionssupportingIPconnectivityincluding6LoWPAN.

• SupportofMeshnetworking.ThisistheonefeaturethatothertechnologieslikeZigBeesupportandisoneofthebiggestrequests.Meshnetworkingenablesseveralnewapplicationareasandcanbeusedtoextendrangeandallowcooperativedevices.SeveralcompanieshaveintroducedproprietaryMeshsolutionsbasedonBluetoothLowEnergy,andtheSIGcommitteesareworkingtopublishonestandardthatwillallowforinteroperability.

• Higherdatarateswithlittle/nopowerincrease,andlongerrangewithsomeincreaseinpower.Bothrespondtonewandexpandedusemodelsandwillenablenewmarketsandapplications.

10Onegoodbeaconarticleforfurtherinformation:https://developer.mbed.org/blog/entry/BLE-Beacons-URIBeacon-AltBeacons-iBeacon/11https://www.bluetooth.com/news/pressreleases/2015/11/11/bluetooth-technology-to-gain-longer-rangefaster-speedand-mesh-networking-in-2016

ConclusionBluetoothisakeytechnologyformobiledevicesandtheIoT.Itisubiquitous,usefulandcool.Throughoutitsdevelopmentithascontinuedtoexpandinitsabilitytoenablenewandsometimesuniqueapplicationsinmobileandlowpowerconnectivity.AtPlugable,wewanttoprovideyouwithcoolandusefulproductstoconnectyouwirelesslyandsupportyourmobileneeds!

Finalnotes• Alltrademarksarepropertyoftheirrespectiveowners.• FormoreinformationonBluetoothtechnology,pleasevisit

www.bluetooth.com• FormoreinformationonWiFitechnology,pleasevisitwww.wi-fi.org• ForinformationaboutPlugableandourproducts,pleasevisit

www.plugable.com