Module-1.pdfbasic networking basic networking

basic networking

1. Basics of Networking
Module-1

2. Introduction
•Presentera-dataandinformation-centricoperations.
•Thequalityofanyparticularinformationisasgoodasthevarietyand
strengthofthedatathatgeneratesthisinformation.
•Thespeedatwhichdataisupdatedtoallmembersofateam(whichmaybe
agroupofindividuals,anorganization,oracountry)dictatestheadvantage
thattheteamhasoverothersingeneratingusefulinformationfromthe
gathereddata.
•Today’sworldreliesheavilyondataandnetworking

3. Introduction (Cont…)
•Networkingreferstothelinkingofcomputersandcommunication
networkdevices(alsoreferredtoashosts),andareseparatedbyunique
deviceidentifiers.
•Thesehostsmaybeconnectedbyasinglepathorthroughmultiple
pathsforsendingandreceivingdata.
•Thedatatransferredbetweenthehostsmaybetext,images,orvideos,
whicharetypicallyintheformofbinarybitstreams

4. Network Types
•Computernetworksareclassifiedaccordingtovariousparameters:
1)Typeofconnection
2)physicaltopologyand
3)reachofthenetwork
•Theseclassificationsarehelpfulindecidingtherequirementsofanetwork
setupandprovideinsightsintotheappropriateselectionofanetworktype
forthesetup

5. I. Connection types
•Depending on the way a host communicates with other hosts
1. Point-to-point and
2. Point-to-multipoint
1.Point-to-point:
oPoint-to-point connections are used to establish direct connections between two hosts.
oThese networks were designed to work over duplex links and are functional for both
synchronous as well as asynchronous systems.

6. 2. Point-to-multipoint:
oMore than two hosts share the same link
oThis type of configuration is similar to the one-to-many connection type
oThe channel is shared between the various hosts

7. (a) Point-to-point (b) Point-to-multipoint

8. II. Physical topology
•Depending on the physical manner in which communication paths between
the hosts are connected, computer networks can have the following four
broad topologies:
1. Star
2. Mesh
3. Bus and
4. Ring

9. 1. Star Topology
•Everyhosthasapoint-to-pointlinktoacentralcontrollerorhub.
•Thehostscannotcommunicatewithoneanotherdirectly;theycan
onlydosothroughthecentralhub.
•Thehubactsasthenetworktrafficexchange.
•Forlarge-scalesystems,thehub,essentially,hastobeapowerful
servertohandleallthesimultaneoustrafficflowingthroughit.
•Astherearefewerlinks,thistopologyischeaperandeasiertoset
up.

10. •Advantagesofthestartopologyareeasyinstallationandtheeaseof
faultidentificationwithinthenetwork.Ifthecentralhubremains
uncompromised,linkfailuresbetweenahostandthehubdonothave
abigeffectonthenetwork,exceptforthehostthatisaffected.
•Disadvantageofthistopologyisthedangerofasinglepointoffailure.
Ifthehubfails,thewholenetworkfails

11. 2. Mesh Topology
•In a mesh topology, every host is connected to
every other host using a dedicated link.
•For n hosts in a mesh, there are a total of
n(n−1)/2 dedicated full duplex links between
the hosts. This massive number of links makes
the mesh topology expensive.

12. •Advantages:
•Robustness and resilience of the system. Even if a link is down or broken, the
network is still fully functional as there remain other pathways for the traffic to
flow through
•The security and privacy of the traffic as the data is only seen by the intended
recipients and not by all members of the network.
•The reduced data load on a single host, as every host in this network takes care
of its traffic load

13. 3. Bus Topology
•Abustopologyfollowsthepoint-to-multipoint
connection.
•Abackbonecableorbusservesastheprimarytraffic
pathwaybetweenthehosts.
•Thehostsareconnectedtothemainbusemploying
droplinesortaps
•Ease of installation

14. •Thereisarestrictiononthelengthofthebusandthenumberofhosts
thatcanbesimultaneouslyconnectedtothebusduetosignallossover
theextendedbus.
•Thebustopologyhasasimplecablingprocedureinwhichasinglebus
(backbonecable)canbeusedforanorganization.
•Multipledroplinesandtapscanbeusedtoconnectvarioushoststo
thebus,makinginstallationveryeasyandcheap.
•However,themaindrawbackofthistopologyisthedifficultyinfault
localizationwithinthenetwork

15. 4. Ring Topology
•Worksontheprincipleofapoint-to-pointconnection.
•Eachhostisconfiguredtohaveadedicatedpoint-to-point
connectionwithitstwoimmediateneighboringhostson
eithersideofitthroughrepeatersateachhost.
•Therepetitionofthissystemformsaring.
•Therepeatersateachhostcapturetheincomingsignal
intendedforotherhosts,regeneratesthebitstream,and
passesitontothenextrepeater.

16. Network Topology Comparison

17. Network Reachability
•Computernetworksaredividedintofourbroadcategoriesbasedon
networkreachability:
1.Personalareanetworks(PAN)
2.Localareanetworks(LAN)
3.Wideareanetworks(WAN)and
4.Metropolitanareanetworks(MAN)

18. Personal area networks (PAN)
•Restricted to individual usage
•PANsarewirelessnetworks,whichmakeuseoflow-rangeandlow-power
technologiessuchasBluetooth.
•ThereachabilityofPANsliesintherangeofafewcentimeterstoafew
meters.
•DatarateinrangeoffewKbps.
•E.g.Connectedwirelessheadphones,wirelessspeakers,laptops,
smartphones

19. Local area networks(LAN)
•Collectionofhostslinkedtoasinglenetworkthroughwiredorwirelessconnections.
•LANsarerestrictedtobuildings,organizations,orcampuses.
•Typically,afewleasedlinesconnectedtotheInternetprovidewebaccesstothewhole
organizationoracampus;
•ThelinesarefurtherredistributedtomultiplehostswithintheLANenablinghosts
•Thepresent-daydataaccessrateswithintheLANsrangefrom100Mbpsto1000Mbps,with
veryhighfault-tolerancelevels.
•CommonlyusednetworkcomponentsinaLANareservers,hubs,routers,switches,terminals,
andcomputers

20. Wide area networks(WAN)
•Connectdiversegeographiclocations.
•Theyarerestrictedwithintheboundariesofastateorcountry.
•ThedatarateofWANsisintheorderofafractionofLAN’sdatarate–10to100Mbps.
•Typically,WANsconnectingtwoLANsorMANsmayusepublicswitchedtelephone
networks(PSTNs)orsatellite-basedlinks.
•Duetothelongtransmissionranges,WANstendtohavemoreerrorsandnoiseduring
transmissionandareverycostlytomaintain.
•ThefaulttoleranceofWANsarealsogenerallylow

21. Metropolitan area networks(MAN)
•ThereachabilityofaMANliesbetweenthatofaLANandaWAN
•MANsconnectvariousorganizationsorbuildingswithinagivengeographiclocationor
city.
•AnexcellentexampleofaMANisanInternetserviceprovider(ISP)supplyingInternet
connectivitytovariousorganizationswithinacity.
•AsMANsarecostly,theymaynotbeownedbyindividualsorevensingleorganizations.
•Typicalnetworkingdevices/componentsinMANsaremodemsandcables.
•Datarate–1Gbpsto100Gbps.
•MANstendtohavemoderatefaulttolerancelevels.

22. Layered Network Models
•Theintercommunicationbetweenhostsinanycomputernetworkis
builtuponthepremiseofvarioustask-specificlayers.
•Traditionallayerednetworkmodels:
1.OSIreferencemodel
2.Internetprotocolsuite

23. OSI Model
•OpenSystemsInterconnection(OSI)modeldescribessevenlayersthat
computersystemsusetocommunicateoveranetwork.
•TheISO-OSImodelisaconceptualframeworkthatpartitionsany
networkedcommunicationdeviceintosevenlayersofabstraction,
eachperformingdistincttasksbasedontheunderlyingtechnologyand
internalstructureofthehosts

26. 1. Physical Layer
•First/LowestlayeroftheOSImodel.
•Responsibleforphysicalconnectionbetweendevices.
•Responsibleforelectricalandmechanicaloperationsofthehostatphysical
level:signalgeneration,signaltransfer,voltages,thelayoutofcables,
physicalportlayout,lineimpedances,andsignalloss.
•Responsibleforthetopologicallayoutofthenetwork(star,mesh,bus,or
ring),communicationmode(simplex,duplex,fullduplex),andbitrate
controloperations

27. 2. Data Link Layer
•Second layer of the model.
•Responsible for the node-to-node delivery of the message.
•The main function of this layer is to make sure data transfer is error-free from one
node to another, over the physical layer
•When a packet arrives in a network, it is the responsibility of DLL to transmit it to
the Host using its MAC address.
•Two sublayers-
1.Logical Link Control (LLC)
2.Media Access Control (MAC)

28. •ThepacketreceivedfromtheNetworklayerisfurtherdividedintoframes
dependingontheframesizeofNIC(NetworkInterfaceCard).
•DLLalsoencapsulatesSenderandReceiver’sMACaddressintheheader.
•TheReceiver’sMACaddressisobtainedbyplacinganARP(Address
ResolutionProtocol)requestontothewireasking“WhohasthatIP
address?”andthedestinationhostwillreplywithitsMACaddress.

29. Network Layer
•Media layer –layer 3.
•Worksforthetransmissionofdatafromonehosttotheotherlocated
indifferentnetworks.
•Italsotakescareofpacketroutingi.e.,selectionoftheshortestpathto
transmitthepacket,fromthenumberofroutesavailable.
•Thesender&receiver’sIPaddressesareplacedintheheaderbythe
networklayer.
•Functions–addressing,sequencingofpackets,congestioncontrol,
errorhandling,andInternetworking.
•Theprotocoldataunitassociatedwiththislayerisreferredtoasa
packet.

30. Transport Layer
•Layer4-hostlayer.
•Tasks-end-to-enderrorrecoveryandflowcontroltoachieveatransparenttransferof
databetweenhosts.
•Thislayerisresponsibleforkeepingtrackofacknowledgmentsduringvariable-length
datatransferbetweenhosts.
•Incaseoflossofdata,orwhennoacknowledgmentisreceived,thetransportlayer
ensuresthattheparticularerroneousdatasegmentisre-senttothereceivinghost.
•Theprotocoldataunitassociatedwiththislayerisreferredtoasasegmentordatagram

31. Session Layer
•Layer5-hostlayer.
•Itisresponsibleforestablishing,controlling,andterminationof
communicationbetweennetworkedhosts,authenticationandsecurity.
•Thesessionlayerseesfullutilizationduringoperationssuchasremote
procedurecallsandremotesessions.
•Theprotocoldataunitassociatedwiththislayerisreferredtoasdata.

32. Presentation Layer
•Hostlayer-layer6.
•Thedatafromtheapplicationlayerisextractedhereandmanipulatedasper
therequiredformattotransmitoverthenetwork.
•Responsiblefordataformatconversionsandencryptiontaskssuchthatthe
syntacticcompatibilityofthedataismaintainedacrossthenetwork,for
whichitisalsoreferredtoasthesyntaxlayer.
•Theprotocoldataunitassociatedwiththislayerisreferredtoasdata.

33. Application Layer
•Layer6-hostlayer.
•Itisdirectlyaccessiblebyanend-userthroughsoftwareAPIs(application
programinterfaces)andterminals.
•Applicationssuchasfiletransfers,FTP(filetransferprotocol),e-mails,andother
suchoperationsareinitiatedfromthislayer.
•Theapplicationlayerdealswithuserauthentication,identificationof
communicationhosts,qualityofservice,andprivacy.
•Theprotocoldataunitassociatedwiththislayerisreferredtoasdata

34. `

35. Internet protocol suite
•TheInternetprotocolsuitepredatestheOSImodelandprovidesonlyfourlevels
ofabstraction:
1.Linklayer
2.Internetlayer
3.Transportlayerand
4.Applicationlayer.
•ThiscollectionofprotocolsiscommonlyreferredtoastheTCP/IPprotocolsuite
asthefoundationtechnologiesofthissuiteareTransmission Control Protocol
(TCP) and Internet Protocol (IP)

37. Link Layer:
•FirstandbaselayeroftheTCP/IPprotocolsuite-NetworkInterfaceLayer.
•Thislayerissynonymouswiththecollectivephysicalanddatalinklayerof
theOSImodel.
•ItenablesthetransmissionofTCP/IPpacketsoverthephysicalmedium.
•Accordingtoitsdesignprinciples,thelinklayerisindependentofthe
mediuminuse,frameformat,andnetworkaccess,enablingittobeused
withawiderangeoftechnologiessuchastheEthernet,wirelessLAN,and
theasynchronoustransfermode(ATM).

38. Internet Layer:
•Layer2oftheTCP/IPprotocolsuiteissynonymoustothenetworklayerof
theOSImodel.
•Itisresponsibleforaddressing,addresstranslation,datapackaging,data
disassemblyandassembly,routing,andpacketdeliverytrackingoperations.
•Somecoreprotocolsassociatedwiththislayerareaddressresolution
protocol(ARP),Internetprotocol(IP),Internetcontrolmessageprotocol
(ICMP),andInternetgroupmanagementprotocol(IGMP).

39. Transport Layer:
•Layer3oftheTCP/IPprotocolsuiteisfunctionallysynonymouswiththetransport
layeroftheOSImodel.
•Functions-errorcontrol,flowcontrol,congestioncontrol,segmentation,and
addressinginanend-to-endmanner;
•Itisalsoindependentoftheunderlyingnetwork.
•Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) arethe
coreprotocolsuponwhichthislayerisbuilt,whichinturnenablesittohavethe
choiceofprovidingconnection-orientedorconnectionlessservicesbetweentwo
ormorehostsornetworkeddevices.

40. Application Layer:
•Layer4oftheTCP/IPprotocolsuitearesynonymouswiththecollective
functionalitiesoftheOSImodel’ssession,presentation,andapplicationlayers.
•Thislayerenablesanend-usertoaccesstheservicesoftheunderlyinglayersand
definestheprotocolsfor the transfer of data.
•Hypertext transfer protocol (HTTP), file transfer protocol (FTP), simple mail
transfer protocol (SMTP), domain name system (DNS), routinginformation
protocol(RIP),andsimplenetworkmanagementprotocol(SNMP)aresomeofthe
coreprotocolsassociatedwiththislayer.

41. Emergence of IoT

42. Introduction
•The present-day Internet allows massivelyheterogeneoustrafficthroughit.
•Thisnetworktrafficconsistsofimages,videos,music,speech,text,numbers,binary
codes,machinestatus,bankingmessages,datafromsensorsandactuators,healthcare
data,datafromvehicles,homeautomationsystemstatusandcontrolmessages,military
communications,andmanymore.
•This hugevarietyofdataisgeneratedfromamassivenumberofconnecteddevices,
whichmaybedirectlyconnectedtotheInternetorconnectedthroughgatewaydevices.

43. •10-yearglobaltrendandprojectionofconnecteddevices(statisticssourcedfrom
the Information Handling Services)

44. TheInternetofThings(IoT)isthenetworkofphysicalobjectsthat
containembeddedtechnologytocommunicateandsenseorinteract
withtheirinternalstatesortheexternalenvironment.“
- Gartner Research

45. •IoTisananytime,anywhere,andanythingnetworkof
Internet-connectedphysicaldevicesorsystemscapableof
sensinganenvironmentandaffectingthesensed
environmentintelligently.
•Thisisgenerallyachievedusinglow-powerandlow-form-
factorembeddedprocessorson-boardthe“things”
connected to the Internet.

46. IoTsystemscanbecharacterizedbythefollowingfeatures:
•Associatedarchitectures,whicharealsoefficientandscalable.
•Noambiguityinnamingandaddressing.
•Massivenumberofconstraineddevices,sleepingnodes,mobiledevices,andnon-
IP devices.
•Intermittentandoftenunstableconnectivity.
IoTisspeculatedtohaveachievedfasterandhighertechnologyacceptanceascompared
toelectricityandtelephony.

47. The compound annual growth rate (CAGR) of the IoT
market
The IoT market share across various industries

48. Evolution of IoT
The sequence of technological developments leading to the shaping
of the modern-day IoT

49. ATM
•ATMsorautomatedtellermachinesarecashdistributionmachines,whicharelinked
toauser’sbankaccount.
•ATMsdispensecashuponverificationoftheidentityofauserandtheiraccount
throughaspeciallycodedcard.
•ThecentralconceptbehindATMswastheavailabilityoffinancialtransactionseven
whenbankswereclosedbeyondtheirregularworkhours.
•TheseATMswereubiquitousmoneydispensers.
•ThefirstATMbecameoperationalandconnectedonlineforthefirsttimein1974

50. Web
•WorldWideWebisaglobalinformationsharingandcommunication
platform.
•TheWebbecameoperationalforthefirsttimein1991.
•Sincethen,ithasbeenmassivelyresponsibleforthemanyrevolutions
inthefieldofcomputingandcommunication

51. SmartMeters
•Theearliestsmartmeterwasapowermeter,whichbecameoperational
inearly2000.
•Thesepowermeterswerecapableofcommunicatingremotelywiththe
powergrid.
•Theyenabledremotemonitoringofsubscribers’powerusageand
easedtheprocessofbillingandpowerallocationfromgrids.

52. DigitalLocks
•Digitallockscanbeconsideredasoneoftheearlierattemptsat
connectedhome-automationsystems.
•Present-daydigitallocksaresorobustthatsmartphonescanbeusedto
controlthem.
•Operationssuchaslockingandunlockingdoors,changingkeycodes,
includingnewmembersintheaccesslists,canbeeasilyperformed,
andthattooremotelyusingsmartphones

53. ConnectedHealthcare
•Healthcaredevicesconnecttohospitals,doctors,andrelativestoalert
themofmedicalemergenciesandtakepreventivemeasures.
•Thedevicesmaybesimplewearableappliances,monitoringjustthe
heartrateandpulseofthewearer,aswellasregularmedicaldevices
andmonitorsinhospitals.
•Theconnectednatureofthesesystemsmakestheavailabilityof
medicalrecordsandtestresultsmuchfaster,cheaper,andconvenient
forbothpatientsaswellashospitalauthorities.

54. ConnectedVehicles
•ConnectedvehiclesmaycommunicatetotheInternetorwithother
vehicles,orevenwithsensorsandactuatorscontainedwithinit.
•Thesevehiclesself-diagnosethemselvesandalertownersabout
systemfailures.

55. SmartCities
•Thisisacity-wideimplementationofsmartsensing,monitoring,and
actuationsystems.
•Thecity-wideinfrastructurecommunicatingamongstthemselves
enablesunifiedandsynchronizedoperationsandinformation
dissemination.
•Someofthefacilitieswhichmaybenefitareparking,transportation,
andothers.

56. SmartDust
•Thesearemicroscopiccomputers.
•Smallerthanagrainofsandeach,theycanbeusedinnumerous
beneficialways,whereregularcomputerscannotoperate.
•Forexample,smartdustcanbesprayedtomeasurechemicalsinthe
soiloreventodiagnoseproblemsinthehumanbody.

57. SmartFactories
•Thesefactoriescanmonitorplantprocesses,assemblylines,distributionlines,
andmanagefactoryfloorsallontheirown.
•Thereductioninmishapsduetohumanerrorsinjudgmentorunoptimized
processesisdrasticallyreduced
UAVs
•UAVsorunmannedaerialvehicleshaveemergedasrobustpublicdomain
solutionstaskedwithapplicationsrangingfromagriculture,surveys,
surveillance,deliveries,stockmaintenance,assetmanagement,andothertasks.

58. Technological interdependencies of IoT with
other domains and networking paradigms
M2M -Machine-to-Machine
CPS -Cyber Physical System
IoE –Internet of Environment
IoP–Internet of People

59. M2M
•TheM2Morthemachine-to-machineparadigmsignifiesasystemof
connectedmachinesanddevices,whichcantalkamongstthemselves
withouthumanintervention.
•Thecommunicationbetweenthemachinescanbeforupdateson
machinestatus(stocks,health,powerstatus,andothers),collaborative
taskcompletion,overallknowledgeofthesystemsandthe
environment,andothers.

60. CPS
•TheCPSorthecyberphysicalsystemparadigminsinuatesaclosed
controlloop—fromsensing,processing,andfinallytoactuation—
usingafeedbackmechanism.
•CPShelpsinmaintainingthestateofanenvironmentthroughthe
feedbackcontrolloop,whichensuresthatuntilthedesiredstateis
attained,thesystemkeepsonactuatingandsensing.
•HumanshaveasimplesupervisoryroleinCPS-basedsystems;most
oftheground-leveloperationsareautomated.

61. IoE
•TheIoEparadigmismainlyconcernedwithminimizingandeven
reversingtheill-effectsofthepermeationofInternet-based
technologiesontheenvironment.
•Themajorfocusareasofthisparadigmincludesmartandsustainable
farming,sustainableandenergy-efficienthabitats,enhancingthe
energyefficiencyofsystemsandprocesses,andothers.
•Inbrief,wecansafelyassumethatanyaspectofIoTthatconcernsand
affectstheenvironment,fallsunderthepurviewofIoE

62. Industry4.0
•Industry4.0iscommonlyreferredtoasthefourthindustrialrevolutionpertaining
todigitizationinthemanufacturingindustry.
•Thepreviousrevolutionschronologicallydealtwithmechanization,mass
production,andtheindustrialrevolution,respectively.
•Thisparadigmstronglyputsforwardtheconceptofsmartfactories,where
machinestalktooneanotherwithoutmuchhumaninvolvementbasedona
frameworkofCPSandIoT.
•ThedigitizationandconnectednessinIndustry4.0translatetobetterresourceand
workforcemanagement,optimizationofproductiontimeandresources,andbetter
upkeepandlifetimesofindustrialsystems.

63. IoP
•IoPisanewtechnologicalmovementontheInternetwhichaimsto
decentralizeonlinesocialinteractions,payments,transactions,and
othertaskswhilemaintainingconfidentialityandprivacyofitsuser’s
data.
•AfamoussiteforIoPstatesthatastheintroductionoftheBitcoinhas
severelylimitedthepowerofbanksandgovernments,theacceptance
ofIoPwilllimitthepowerofcorporations,governments,andtheirspy
agencies

64. IoT versus M2M
•M2M-communicationsandinteractionsbetweenvariousmachines
anddevices.
•Theseinteractionscanbeenabledthroughacloudcomputing
infrastructure,aserver,orsimplyalocalnetworkhub.
•M2Mcollectsdatafrommachineryandsensors,whilealsoenabling
devicemanagementanddeviceinteraction.
•TelecommunicationservicesprovidersintroducedthetermM2M,and
technicallyemphasizedonmachineinteractionsviaoneormore
communicationnetworks(e.g.,3G,4G,5G,satellite,public
networks).
•M2MispartoftheIoTandisconsideredasoneofitssub-domains.

65. •M2MstandardsoccupyacoreplaceintheIoTlandscape.
•However,intermsofoperationalandfunctionalscope,IoTisvaster
thanM2Mandcomprisesabroaderrangeofinteractionssuchasthe
interactionsbetweendevices/things,things,andpeople,thingsand
applications,andpeoplewithapplications.
•M2Menablestheamalgamationofworkflowscomprisingsuch
interactionswithinIoT.
•InternetconnectivityiscentraltotheIoTthemebutisnotnecessarily
focusedontheuseoftelecomnetworks.

66. IoT versus CPS
•Cyberphysicalsystems(CPS)encompassessensing,control,
actuation,andfeedbackasacompletepackage.
•Inotherwords,adigitaltwinisattachedtoaCPS-basedsystem.
•Digitaltwinisavirtualsystem–modelrelation,inwhichthesystem
signifiesaphysicalsystemorequipmentorapieceofmachinery,
whilethemodelrepresentsthemathematicalmodelorrepresentation
ofthephysicalsystem’sbehaviororoperation.
•Manyatime,adigitaltwinisusedparalleltoaphysicalsystem,
especiallyinCPSasitallowsforthecomparisonofthephysical
system’soutput,performance,andhealth.

67. •Basedonfeedbackfromthedigitaltwin,aphysicalsystemcanbe
easilygivencorrectivedirections/commandstoobtaindesirable
outputs.
•Incontrast,theIoTparadigmdoesnotcompulsorilyneedfeedbackor
adigitaltwinsystem.
•IoTismorefocusedonnetworkingthancontrols.
•Someoftheconstituentsub-systemsinanIoTenvironmentmay
includefeedbackandcontrolstoo.
•Inthislight,CPSmaybeconsideredasoneofthesub-domainsofIoT

68. IoT versus WoT
•WebofThings(WoT)paradigmenablesaccessandcontroloverIoTresourcesand
applications.
•Theseresourcesandapplicationsaregenerallybuiltusingtechnologiessuchas
HTML5.0,JavaScript,Ajax,PHP,andothers.
•REST(representationalstatetransfer)isoneofthekeyenablersofWoT.
•TheuseofRESTfulprinciplesandRESTfulAPIs(applicationprograminterface)
enablesbothdevelopersanddeployerstobenefitfromtherecognition,acceptance,
andmaturityofexistingwebtechnologieswithouthavingtoredesignandredeploy
solutionsfromscratch

69. •Still,designingandbuildingtheWoTparadigmhasvariousadaptabilityand
securitychallenges,especiallywhentryingtobuildagloballyuniformWoT.
•AsIoTisfocusedoncreatingnetworkscomprisingobjects,things,people,
systems,andapplications,whichoftendonotconsidertheunificationaspect
andthelimitationsoftheInternet,theneedforWoT,whichaimstointegrate
thevariousfocusareasofIoTintotheexistingWebisreallyinvaluable.
•Technically,WoTcanbethoughtofasanapplicationlayer-basedhatadded
overthenetworklayer.
•ScopeofIoTapplicationsismuchbroader.

70. Enabling IoT and the Complex Interdependence
of Technologies
•IoTparadigmintofourplanes:
1.Services
2.Localconnectivity
3.Globalconnectivity,and
4.Processing

72. Service Plane
•Composedoftwoparts:
1.Thingsordevicesand
2.Low-powerconnectivity
•IoTapplicationrequiresthebasicsetupofsensing,followedbyrudimentary
processing(often),andalow-power,low-rangenetwork,whichismainly
builtupontheIEEE802.15.4protocol.
•The things - wearables, computers, smartphones, household appliances,
smart glasses, factory machinery, vending machines, vehicles, UAVs,
robots, and other such contraptions.

73. •Low-powerconnectivity-responsibleforconnectingthethingsin
localimplementation,maybelegacyprotocolssuchasWiFi,
Ethernet,orcellular.
•Modern-daytechnologiesaremainlywirelessandoften
programmablesuchasZigbee,RFID,Bluetooth,6LoWPAN,LoRA,
DASH,Insteon,andothers.
•Theyareresponsiblefortheconnectivitybetweenthethingsofthe
IoTandthenearesthuborgatewaytoaccesstheInternet.

74. LocalConnectivity
•ResponsiblefordistributingInternetaccesstomultiplelocalIoT
deployments.
•Thisdistributionmaybeonthebasisofthephysicalplacementofthe
things,onthebasisoftheapplicationdomains,orevenonthebasisof
providersofservices.
•Servicessuchasaddressmanagement,devicemanagement,security,sleep
scheduling,andothersfallwithinthescopeofthisplane.
•ThisplanefallsunderthepurviewofIoTmanagementasitdirectlydeals
withstrategiestouse/reuseaddressesbasedonthingsandapplications.

75. GlobalConnectivity
•PlaysasignificantroleinenablingIoTintherealsensebyallowingfor
worldwideimplementationsandconnectivitybetweenthings,users,
controllers,andapplications.
•ThisplanealsofallsunderthepurviewofIoTmanagementasitdecides
howandwhentostoredata,whentoprocessit,whentoforwardit,andin
whichformtoforwardit.
•TheWeb,data-centers,remoteservers,Cloud,andothersmakeupthis
plane.

76. •Theparadigmof“fogcomputing”liesbetweentheplanesoflocal
connectivityandglobalconnectivity.
•Itoftenservestomanagetheloadofglobalconnectivityinfrastructure
byoffloadingthecomputationnearertothesourceofthedataitself,
whichreducesthetrafficloadontheglobalInternet.

77. Processing
•ThemembersinthisplanemaybetermedasIoTtools,simplybecause
theywring-outusefulandhuman-readableinformationfromallthe
rawdatathatflowsfromvariousIoTdevicesanddeployments.
•Thevarioussub-domainsofthisplaneinclude
•Intelligence
•Conversion(dataandformatconversion,anddatacleaning),
learning(makingsenseoftemporalandspatialdatapatterns)

78. •Cognition(recognizingpatternsandmappingittoalreadyknownpatterns),
algorithms(variouscontrolandmonitoringalgorithms)
•Visualization(renderingnumbersandstringsintheformofcollectivetrends,
graphs,charts,andprojections),and
•Analysis((estimatingtheusefulnessofthegeneratedinformation,making
senseoftheinformationwithrespecttotheapplicationandplaceofdata
generation,andestimatingfuturetrendsbasedonpastandpresentpatternsof
informationobtained).
•Variouscomputingparadigmssuchas“bigdata”,“machine
Learning”,andothers,fallwithinthescopeofthisdomain.

79. IoT Networking Components
•An IoT implementation is composed of several components, which may vary with their
application domains.
•The broad components that come into play during the establishment of any IoT network,
into six types:
1.IoT node
2.IoT router
3.IoT LAN
4.IoT WAN
5.IoT gateway, and
6.IoT proxy

80. A typical IoT network ecosystem highlighting the various networking
components—from IoT nodes to the Internet

81. IoT Node:
•ThenetworkingdeviceswithinanIoTLAN.
•Eachofthesedevicesistypicallymadeupofasensor,aprocessor,anda
radio,whichcommunicateswiththenetworkinfrastructure(eitherwithin
theLANoroutsideit).
•ThenodesmaybeconnectedtoothernodesinsideaLANdirectlyorby
meansofacommongatewayforthatLAN.ConnectionsoutsidetheLAN
arethroughgatewaysandproxies.

82. IoT Router:
•AnIoTrouterisapieceofnetworkingequipmentthatisprimarily
taskedwiththeroutingofpacketsbetweenvariousentitiesintheIoT
network;
•Itkeepsthetrafficflowingcorrectlywithinthenetwork.
•Aroutercanberepurposedasagatewaybyenhancingits
functionalities.

83. IoTLAN:
•Thelocalareanetwork(LAN)enableslocalconnectivitywithinthe
purviewofasinglegateway.
•Typically,theyconsistofshort-rangeconnectivitytechnologies.
•IoTLANsmayormaynotbeconnectedtotheInternet.
•Generally,theyarelocalizedwithinabuildingoranorganization.

84. IoTWAN:
•Thewideareanetwork(WAN)connectsvariousnetworksegmentssuchas
LANs.
•Theyaretypicallyorganizationallyandgeographicallywide,withtheir
operationalrangelyingbetweenafewkilometerstohundredsofkilometers.
•IoTWANsconnecttotheInternetandenableInternetaccesstothesegments
theyareconnecting.

85. IoTGateway:
•AnIoTgatewayissimplyarouterconnectingtheIoTLANtoaWAN
ortheInternet.
•GatewayscanimplementseveralLANsandWANs.
•TheirprimarytaskistoforwardpacketsbetweenLANsandWANs,
andtheIPlayerusingonlylayer3.

86. IoTProxy:
•Proxiesactivelylieontheapplicationlayerandperformsapplication
layerfunctionsbetweenIoTnodesandotherentities.
•Typically,applicationlayerproxiesareameansofprovidingsecurity
tothenetworkentitiesunderit;
•Ithelpstoextendtheaddressingrangeofitsnetwork.