network-technology

THEBASICTECHNOLOGYOFTHECOMPUTERNETWORK高言0994050613郑帅0994050704张久强0994050605王文琦0994050623马腾跃09940506171.TheBeginningofComputerNetworking.2.TheComponentofaNetwork.3.LANvsWAN.4.Theapplicationofcomputernetworking.5.Video:SocialNetworkingTheBeginningofComputerNetworkingAlittlemorethantwodecadesago,sendingamemo(备忘录)toeveryoneinalargebusinessofficeusedtobedelegated(委托)toaseparatedepartmentwithinthecompany.Todayexecutivescommunicatewiththeirofficeemployeesviaemail,sentwithjustaclickofamouse;thankstocomputernetworking.Intheearly1980s,standalone(单独的)computersgaveuserstheabilitytocreatedocuments,databaseorspreadsheets;thesedocumentswerethensavedonafloppydiskforfutureuse.Unlessaprinterwasattachedtothecomputerfromwhichthesedocumentswerecreated,theywouldbeunabletoprintthemrightaway.However,clientsonanetworkedcomputercansendbothe-mailtohundredsofrecipientsandprintdocumentswithouteverleavingtheirstation.Acomputernetwork,therefore,allowsagroupofcomputerstolinktoeachother’sresourcesforthepurposeofsharingthem,thussavingtimeandmoney.TheComponentofaNetworkNetwork,largeandsmallaremadeupof3primarycomponents,namely:Servers,Clientsorworkstations,andresources.Serversarethecore(核心)componentsofanetworkandtheycomeindifferentshapesandsizes.Themainpurposeofserversistoprovidealinktoresourcesnecessarytoperformatask;theyofferdirectionstotheclientcomputersregardingwheretogotogetwhattheyneed.Therearetwotypesofservers:dedicated(专用)serversandnondedicatedservers.Workstationsarethecomputersonwhichnetworkusersdotheirwork.Thisworkincludeswordprocessing,e-mail,databasedesignoranyothercomputer-relatedpersonaltasks.Inorderforaclientorworkstationtocommunicatewithaserver,itmusthaveanetworkinterface(接口)card,alsoknownasNIC(newlyindustrializingcountry).ThiscardisusuallyinstalledinoneoftheexpansionslotsinsideaPC.Itmustalsohavespecialsoftwarecalledclientsoftwarethatallowsittotalktoserversandrequestresourcesfromthem.And,itmustbeconnectedtoacablingsystem(电缆线路系统)thatconnectsittoanothercomputer.Resources:Aresourceonanetworkisanyitemthatcanbeusedonanetwork.Foranetworktobefullyfunctionalthesethreecomponentsmustnotonlybepresent,theymustworktogether.LANvsWANLANisLocalAreaNetwork’sabbreviation.Localareanetwork,initsearliestdevelopment,wastoconnectallcomputersinasingleofficeonly.ThefirstLANprogram,ShareNetintroducedbyNovell,Inc.Couldonlycoverasinglefloorofanofficebuilding.Moreover,itonlyallowedjustoneuseratatimetoaccessanyresourcesonthenetworkusingtheconcept(概念)knownasfilelocking.Bythelate1980s,therewasagrowingneedfornetworkstosupportmultipleusersandcoverlargergeographicalarea.Althoughthesecapabilitiesexistedinmainframeenvironments,businesseswereunabletoprocurethistypeofsystembecauseoftheprohibitivecostatthattime;indeed,onlyveryfewgovernmentsindevelopednationswereabletoaffordthem.Eventhen,itsefficiencyleftmuchtobedesired.WANisWideAreaNetwork’sabbreviationAsLANtechnologyevolved,wideareanetworks(WAN)cametobeingandsoonbusinesseswithofficesnearandfarwereabletocommunicateasiftheywereinthesameroom.WANrevolutionizedthewaytheworlddoesbusiness;andcurrently,theWorldWideWeb()isthelargestandbest-knownWANofall.WhereasLANwaslimitedto,atmost,asinglebuilding,WANcoveredstates,countriesandcontinents.Tel:8800Theapplicationofcomputernetworking•BusinessApplications•HomeApplications•MobileUsers•BroadcastNetworksBusinessApplicationsofNetworks•Anetworkwithtwoclientsandoneserver.BusinessApplicationsofNetworks(2)•Theclient-servermodelinvolvesrequestsandreplies.HomeNetworkApplications•Accesstoremoteinformation•Person-to-personcommunication•Interactive(互动的)entertainment•ElectroniccommerceHomeNetworkApplications(2)•Inpeer-to-peer(对等层的网络)systemtherearenofixedclientsandservers.HomeNetworkApplications(3)•Someformsofe-commerce.MobileNetworkUsers•Combinationsofwirelessnetworksandmobilecomputing.BroadcastNetworks•Typeoftransmissiontechnology•Broadcastlinks•Point-to-pointlinksBroadcastNetworks(2)•Classification(分类)ofinterconnectedprocessorsbyscale.Whatthevideotalkabout?ThisvideointroducesthebasicideasbehindSocialNetworking.Itfocusesontheroleofsocialnetworkinginsolvingreal-worldproblems,including:TheroleofpeoplenetworksinbusinessandpersonallifeThehiddennatureofreal-worldpeoplenetworksHowsocialnetworkingsitesrevealhiddenconnectionsThebasicfeaturesofsocialnetworkingwebsites