History of cloud computing

the begining of cloud computing

1. History of Cloud Computing
Oneofthefirstquestionsaskedwiththeintroductionofa
newtechnologyis:“Whenwasitinvented?”Other
questionslike“Whenitwasfirstmentioned?”and“What
aretheprospectsforitsfuture?”arealsocommon.
Whenwethinkofcloudcomputing,wethinkofsituations,
productsandideasthatstartedinthe21stcentury.
Thisisnotexactlythewholetruth.
Cloudconceptshaveexistedformanyyears.

2. Cloud Computing
Cloud computing shares characteristics with:
Client–servermodel—Client–servercomputingrefers
broadlytoanydistributedapplicationthatdistinguishes
betweenserviceproviders(servers)andservicerequestors
(clients).
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Gridcomputing—"Aformofdistributedandparallel
computing,wherebya'superandvirtualcomputer'is
composedofaclusterofnetworked,looselycoupled
computersactinginconcerttoperformverylargetasks."
Mainframecomputer—Powerfulcomputersusedmainly
bylargeorganizationsforcriticalapplications,typicallybulk
dataprocessingsuchas:census;industryandconsumer
statistics;policeandsecretintelligenceservices;enterprise
resourceplanning;andfinancialtransactionprocessing.

3. Cloud Computing
Utilitycomputing—The"packagingofcomputing
resources,suchascomputationandstorage,asa
meteredservicesimilartoatraditionalpublic
utility,suchaselectricity."
Peer-to-peer—Adistributedarchitecture
withouttheneedforcentralcoordination.
Participantsarebothsuppliersandconsumersof
resources(incontrasttothetraditionalclient–
servermodel).

4. Cloud Computing
Cloudcomputingisatermusedtorefertoamodelof
networkcomputingwhereaprogramorapplicationrunsona
connectedserverorserversratherthanonalocalcomputing
devicesuchasaPC,tabletorsmartphone.
Likethetraditionalclient-servermodeloroldermainframe
computing,auserconnectswithaservertoperformatask.
Thedifferencewithcloudcomputingisthatthecomputing
processmayrunononeormanyconnectedcomputersatthe
sametime,utilizingtheconceptofvirtualization.

5. Cloud Computing
CloudComputingisatermusedtorefertoa
modelofnetworkcomputingwhereaprogramor
applicationrunsonaconnectedserverorservers
ratherthanonalocalcomputingdevicesuchasaPC,
tabletorsmartphone.
CloudComputingreferstoapplicationsand
servicesthatrunonadistributednetworkusing
virtualizedresourcesandaccessedbycommonInternet
protocolsandnetworkingstandards.

6. Cloud Computing
Inthischapter,youlearnabouttwodifferentclassesof
clouds:thosebasedonthedeploymentmodelandthose
basedontheservicemodel.
TheDeploymentmodeltellsyouwherethecloudis
locatedandforwhatpurpose.
Public,private,community,andhybridcloudsare
deploymentmodels.
Servicemodelsdescribethetypeofservicethatthe
serviceproviderisoffering.Thebest-knownservicemodels
areSoftwareasaService,PlatformasaService,and
InfrastructureasaService—theSPImodel.
Theservicemodelsbuildononeanotheranddefinewhat
avendormustmanageandwhattheclient'sresponsibilityis.

7. Cloud Computing
Theuseoftheword“cloud”makesreferencetothetwo
essentialconcepts:
•Abstraction:
Cloudcomputingabstractsthedetailsofsystem
implementationfromusersanddevelopers.
Applicationsrunonphysicalsystemsthataren'tspecified,
dataisstoredinlocationsthatareunknown,administration
ofsystemsisoutsourcedtoothers,andaccessbyusersis
ubiquitous(everywhere).
•Virtualization:
Cloudcomputingvirtualizessystemsbypoolingandsharing
resources.
Systemsandstoragecanbeprovisionedasneededfroma
centralizedinfrastructure,costsareassessedonametered
basis,multi-tenancyisenabled,andresourcesarescalable
withagility(quickness).

9. Cloud Computing

10. Characteristics of Cloud Computing

11. Cloud Components