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Unit2TextBThreearchitecturalmodelsofe-businessThereareanumberofcommonlyusedcomponentarchitecturalmodelstatcanbeusedasstartingpointforbuildingablueprint.Forsomeimplementationsasinglemodelwillsuffi__.For__nyhoweverseveralofthesearchitecturalmodelswilltobecombinedtoformamoresophisticatede-businessblueprint.Eachofthedefinedbusinesspro__ssesthatneedtobecapturedinthise-businesssolutionshouldbereviewedandtheappropriatemodelselected.Web-server-__ntricArchitecturalModelsBecausee-businesssolutionsh__estemmedfromtheexplosivegrowthoftheweb.Thereareseveralmodelsbasedaroundwebserversthath__ebeenimplementedsuc__ssfullyin__nyorganizationsseefigure1Infigure1a“servi__”mightbehomegrownbusinesslogicoraninte_____toanexistinglegacysystemorpackagedapplicationeitherwithinyourorganizationorbelongingtoathird_____.Therearetwocommonreasonsforplacingbusinesslogicintoservi__sratherthanthewebserveritself.Firstitallowsthelogictobeac__ssedfromsour__sotherthanwebclients.Seconditallowsforamorescalableflexibleand__nageableruntimeenviro__entalbeitmorecomplex.Thearchitecturalmodelsinfigure1canhandle__nye-commer__solutionrequirementsaswellassolutionsthatrequireexposinginternalsystemstoandusersoutsidetheorganizationorinotherpartsoftheenterprise.ArchitecturalmodelsbeyondthewebserverForsometypesofe-businesssolutionsthewebserverisn’tpractical.Forexampletheremightbeabusinessrequirementthatusersbeallowedtopro__ssofflineortheremightbeapplicationsthatmusttransfercomplicateddatastructuresorthath__einteractionsnotwellsuitedtoawebserver’srequest/responseprotocol.Orit__ysimplybethatthee-businesssolutionmustcommunicatewithclientsorpeersthatarenotcapableofcommunicatingviaawebserverprotocolseefigure
20.Intheses__nariosthe“application”couldbeaclientsimilartoawebbrowser.InfactappletsorActiveXcontrolsdownloadedandexecutinginsidebrowsersmightuseoneofthesemodelstocommunicatebacktoservi__swithintheenterprisebypassingthewebserver.Alternativelytheseapplicationscouldbeintegrationpointsintoathird_____’spreexistingapplicationorthese“applications”arepersonaldigitalassistantPDAdevi__sthatneedtobeintegratedintothee-businesssolution.A__jorchallengeassociatedwithusingsucharchitecturesovertheinternetasopposedtoanintranetorextranetissecurity.Mostorganizationsblockallbutafewprotocolsfrommovingacrosstheirfirewalls.Unlessthecomponentsarecommunicatingwithoneofthe“allowed”protocolsusuallyHTTPSSLFTPand__TPdeployingovertheInternet__ynotbepossible;aprivateconnectionwouldberequired.ConsolidatingArchitecturalModelsFigure3illustratestheconsolidationofarchitecturalmodels.Allthemodelsselectedintheprevioussectiontorepresentthevariousbusinesspro__ssesshouldbepla__dintoasinglediagram.Eachservi__orapplicationshouldbelabeledasabusinesslogiccomponentorwiththenameoftheexistingtechnologyorsystemitrepresents.Eachlinkshouldbelabeledas“request/response”or“message”alongwiththebusinesspro__ssitrepresentsandthetypeofnetworkitwillrunover:intranetextranetorinternet.Usemultiplenetworksifapplicable.Whileassemblingthearchitecturalmodelsintoasinglediagramconsolidateduplicateitemsintoone.Forexamplethereshouldbeonlyonewebserverinthisnewdiagramandonebillingsystem.Anyplatformrequirementfor__rtainmodelsshouldbenotedatthistimee.g.integratingwithathird-_____applicationthatrunsonlyonwindowsNT.Somee-businesssolutionswillconsolidateneatlyandresultinaclear______blueprint.Otherswillpresentimmediatechallengessuchasintegrationwithmultiplelegacysystems.Theseissuesshouldberesolvedbeforepro__eding;intheexampleoflegacysystemintegrationEAI____ysisanddesigncanbeappliedtorevisethearchitecturaldiagram.。