计算机网络-外文文献-外文翻译-英文文献-新技术的计算机网络

NewtechniqueofthecomputernetworkAbstractThe21centuryisanagesoftheinformationeconomy,beingthecomputernetworktechniqueofrepresentativetechniquesthisages,willbeatveryfastspeeddevelopsoonincontinuouslycreatively,andwillgodeepintothepeople'swork,lifeandstudy.Therefore,controlthistechniqueandthenseemtobemoretodelivertheimportance.NowImainlyintroducethenewtechniqueofafewnetworksinactualityliveofapplication.keywordsInternetNetworkSystemDigitalCertificatesGridStorage1.ForewordInternetturns36,stillaworkinprogressThirty-sixyearsaftercomputerscientistsatUCLAlinkedtwobulkycomputersusinga15-footgraycable,testinganewwayforexchangingdataovernetworks,whatwouldultimatelybecometheInternetremainsaworkinprogress.Universityresearchersareexperimentingwithwaystoincreaseitscapacityandspeed.ProgrammersaretryingtoimbueWebpageswithintelligence.Andworkisunderwaytore-engineerthenetworktoreduceSpam(junkmail)andsecuritytroubles.Allthewhilethreatsloom:Criticswarnthatcommercial,legalandpoliticalpressurescouldhinderthetypesofinnovationsthatmadetheInternetwhatitistoday.StephenCrockerandVintonCerfwereamongthegraduatestudentswhojoinedUCLAprofessorLenKleinrockinanengineeringlabonSept.2,1969,asbitsofmeaninglesstestdataflowedsilentlybetweenthetwocomputers.ByJanuary,threeothernodesjoinedthefledglingnetwork.Thencamee-mailafewyearslater,acorecommunicationsprotocolcalledTCP/IPinthelate70s,thedomainnamesysteminthe80sandtheWorldWideWeb-nowthesecondmostpopularapplicationbehinde-mail-in1990.TheInternetexpandedbeyonditsinitialmilitaryandeducationaldomainintobusinessesandhomesaroundtheworld.Today,CrockercontinuesworkontheInternet,designingbettertoolsforcollaboration.AndassecuritychairmanfortheInternet'skeyoversightbody,heistryingtodefendthecoreaddressingsystemfromoutsidethreats.HeacknowledgestheInternethehelpedbuildisfarfromfinished,andchangesareinstoretomeetgrowingdemandsformultimedia.Networkprovidersnowmakeonlybesteffortsatdeliveringdatapackets,andCrockersaidbetterguaranteesareneededtopreventtheskipsandstuttersnowcommonwithvideo.Cerf,nowatMCIInc.,saidhewishedhecouldhavedesignedtheInternetwithsecuritybuilt-in.MicrosoftCorp.YahooInc.andAmericaOnlineInc.,amongothers,arecurrentlytryingtoretrofitthenetworksoe-mailsenderscanbeauthenticated-awaytocutdownonjunkmessagessentusingspoofedaddresses.Manyfeaturesbeingdevelopedtodaywouldn'thavebeenpossibleatbirthgiventheslowercomputingspeedsandnarrowerInternetpipes,orbandwidth,Cerfsaid.2.DigitalCertificatesDigitalcertificatesaredatafilesusedtoestablishtheidentityofpeopleandelectronicassetsontheInternet.Theyallowforsecure,encryptedonlinecommunicationandareoftenusedtoprotectonlinetransactions.Digitalcertificatesareissuedbyatrustedthirdpartyknownasacertificationauthority(CA).TheCAvalidatestheidentityofacertificateholderand“signs”thecertificatetoattestthatithasn’tbeenforgedoralteredinanyway.NewUsesForDigitalCertificatesDigitalcertificatesarenowbeingusedtoprovidesecurityandvalidationforwirelessconnections,andhardwaremanufacturersareoneofthelatestgroupstousethem.Notlongago,VersionInc.announceditsCableModemAuthenticationServices,whichallowhardwaremanufacturerstoembeddigitalcertificatesintocablemodemstohelppreventthepiratingofbroadbandservicesthroughdevicecloning.UsingVersionsoftware,hardwaremakerscangeneratecryptographickeysandcorrespondingdigitalcertificatesthosemanufacturersorcableserviceproviderscanusetoautomaticallyidentifyindividualmodems.This‘ast-mile’authenticationnotonlyprotectsthevalueofexistingcontentandservicesbutalsopositionscablesystemoperatorstobringabroadnewrangeofcontent,applicationsandvalue-addedservicestomarket.WhenaCAdigitallysignsacertificate,itsownercanuseitasanelectronicpassporttoprovehisidentity.ItcanbepresentedtoWebsites,networksorindividualsthatrequiresecureaccess.Identifyinginformationembeddedinthecertificateincludestheholder’snameande-mailaddress,thenameoftheCA,aserialnumberandanyactivationorexpirationdataforthecertificate.WhentheCAverifiesauser’sidentity,thecertificateusestheholder’spublicencryptionkeytoprotectthisdata.CertificatesthataWebserverusestoconfirmtheauthenticityofaWebsiteforauser’sbrowseralsoemploypublickeys.WhenauserwantstosendconfidentialinformationtoaWebserver,suchasacredit-cardnumberforanonlinetransaction,thebrowserwillaccessthepublickeyintheserver’sdigitalcertificatetoverifyitsidentity.RoleofPublic-KeyCryptographyThepublickeyisonehalfofapairofkeysusedinpublic-keycryptography,whichprovidesthefoundationfordigitalcertificates.Public-keycryptographyusesmatchedpublicandprivatekeysforencryptionanddecryption.Thesekeyshaveanumericalvaluethat’susedbyanalgorithmtoscrambleinformationandmakeitreadableonlytouserswiththecorrespondingdecryptionkey.Otherstoencryptinformationmeantonlyforthatpersonuseaperson’spublickey.Whenhereceivestheinformation,heuseshiscorrespondingprivatekey,whichiskeptsecret,todecryptthedata.Aperson'spublickeycanbedistributedwithoutdamagingtheprivatekey.AWebserverusingadigitalcertificatecanuseitsprivatekeytomakesurethatonlyitcandecryptconfidentialinformationsenttoitovertheInterne