計(jì)算機(jī)網(wǎng)絡(luò)專業(yè)英語(yǔ) 習(xí)題及答案匯 許勇 測(cè)試題1-18

NOSInaddition,anetworkcanbesetupbycomputerswithNOSsuchasWindows/Linuxinstalled.EverycomputerrequiresauniqueLANcard,whichshouldbeproperlyinstalledandconfigured,andEthernetcablewiththeRJ-45connectorsatbothends.Tocommunicatewiththeothercomputer,eachcomputershouldsupportthesameprotocolandtheTCP/IPisthemostcommonlyusedprotocolinacomputernetwork.Eachnetworkiseitherapeer-to-peerorclient/servernetwork.Inaclient/servernetworkmodel,acentralizeddomaincontrollerisusedtocontrolallthecomputernetworks.Itprovidestheservicestotheclientslikelogon,authentication,printeraccess,scanneraccess,centralizeddatastorage,usermanagement,resourcesmanagement,DHCP,DNS,FTPandinternetaccess.InternetTheInternetistheglobalsystemofinterconnectedcomputernetworksthatusetheInternetprotocolsuite(TCP/IP)tolinkbillionsofdevicesworldwide.Itisanetworkofnetworksthatconsistsofmillionsofprivate,public,academic,business,andgovernmentnetworksoflocaltoglobalscope,linkedbyabroadarrayofelectronic,wireless,andopticalnetworkingtechnologies.TheInternetcarriesanextensiverangeofinformationresourcesandservices,suchastheinter-linkedhypertextdocumentsandapplicationsoftheWorldWideWeb(WWW),electronicmail,telephony,andpeer-to-peernetworksforfilesharing.AlthoughtheInternetprotocolsuitehasbeenwidelyusedbyacademiaandthemilitaryindustrialcomplexsincetheearly1980s,eventsofthelate1980sand1990ssuchasmorepowerfulandaffordablecomputers,theadventoffiberoptics,thepopularizationofHTTPandtheWebbrowser,andapushtowardsopeningthetechnologytocommerceeventuallyincorporateditsservicesandtechnologiesintovirtuallyeveryaspectofcontemporarylife.TheoriginsoftheInternetdatebacktoresearchanddevelopmentcommissionedbytheUnitedStatesgovernment,theGovernmentoftheUKandFranceinthe1960stobuildrobust,fault-tolerantcommunicationviacomputernetworks.Thiswork,ledtotheprimaryprecursornetworks,theARPANET.Theinterconnectionofregionalacademicnetworksinthe1980smarksthebeginningofthetransitiontothemodernInternet.Fromthelate1980sonward,thenetworkexperiencedsustainedexponentialgrowthasgenerationsofinstitutional,personal,andmobilecomputerswereconnectedtoit.Mosttraditionalcommunicationmedia,includingtelephonyandtelevision,arebeingreshapedorredefinedbytheInternet,givingbirthtonewservicessuchasInternettelephonyandInternettelevision.Newspaper,book,andotherprintpublishingareadaptingtowebsitetechnology,orarereshapedintobloggingandwebfeeds.TheentertainmentindustrywasinitiallythefastestgrowingsegmentontheInternet.TheInternethasenabledandacceleratednewformsofpersonalinteractionsthroughinstantmessaging,Internetforums,andsocialnetworking.Onlineshoppinghasgrownexponentiallybothformajorretailersandsmallartisansandtraders.Business-to-businessandfinancialservicesontheInternetaffectsupplychainsacrossentireindustries.TheInternethasnocentralizedgovernanceineithertechnologicalimplementationorpoliciesforaccessandusage;eachconstituentnetworksetsitsownpolicies.OnlytheoverreachingdefinitionsofthetwoprincipalnamespacesintheInternet,theInternetProtocoladdressspaceandtheDomainNameSystem(DNS),aredirectedbyamaintainerorganization,theInternetCorporationforAssignedNamesandNumbers(ICANN).ThetechnicalunderpinningandstandardizationofthecoreprotocolsisanactivityoftheInternetEngineeringTaskForce(IETF),anon-profitorganizationoflooselyaffiliatedinternationalparticipantsthatanyonemayassociatewithbycontributingtechnicalexpertise.WirelessLocalAreaNetwork

(WLAN)A

wirelesslocalareanetwork

(WLAN)isa

wirelesscomputernetwork

thatlinkstwoormoredevicesusingawirelessdistributionmethodwithina

limitedarea

suchasahome,school,computerlaboratory,orofficebuilding.Thisgivesuserstheabilitytomovearoundwithinalocalcoverageareaandstillbeconnectedtothenetwork,andcanprovideaconnectiontothewider

Internet.MostmodernWLANsarebasedon

IEEE802.11

standards,marketedunderthe

Wi-Fi

brandname.WirelessLANshavebecomepopularinthehomeduetoeaseofinstallationanduse,andincommercialcomplexesofferingwirelessaccesstotheircustomers,oftenforfree.

NewYorkCity,forinstance,hasbegunapilotprogramtoprovidecityworkersinallfiveboroughsofthecitywithwirelessInternetaccess.The

IEEE802.11

hastwobasicmodesofoperation:

infrastructure

and

adhoc

mode.In

adhoc

mode,mobileunitstransmitdirectlypeer-to-peer.Ininfrastructuremode,mobileunitscommunicatethroughan

accesspoint

thatservesasabridgetoothernetworks(suchas

Internet

or

LAN).SincewirelesscommunicationusesamoreopenmediumforcommunicationincomparisontowiredLANs,the802.11designersalsoincludedencryptionmechanisms:

WiredEquivalentPrivacy

(WEP,nowinsecure),

Wi-FiProtectedAccess

(WPA,WPA2),tosecurewirelesscomputernetworks.Manyaccesspointswillalsooffer

Wi-FiProtectedSetup,aquick(butnowinsecure)methodofjoininganewdevicetoanencryptednetwork.Intelecommunications,5Gisthefifth-generationtechnologystandardforcellularnetworks,whichcellularphonecompaniesbegandeployingworldwidein2019,theplannedsuccessortothe4Gnetworkswhichprovideconnectivitytomostcurrentcellphones.Likeitspredecessors,5Gnetworksarecellularnetworks,inwhichtheserviceareaisdividedintosmallgeographicalareascalledcells.All5GwirelessdevicesinacellareconnectedtotheInternetandtelephonenetworkbyradiowavesthroughalocalantennainthecell.Themainadvantageofthenewnetworksisthattheywillhavegreaterbandwidth,givinghigherdownloadspeeds,eventuallyupto10gigabitspersecond(Gbit/s).Duetotheincreasedbandwidth,itisexpectedthatthenewnetworkswillnotjustservecellphoneslikeexistingcellularnetworks,butalsobeusedasgeneralinternetserviceprovidersforlaptopsanddesktopcomputers,competingwithexistingISPssuchascableinternet,andalsowillmakepossiblenewapplicationsininternetofthings(IoT)andmachinetomachineareas.Current4Gcellphoneswillnotbeabletousethenewnetworks,whichwillrequirenew5Genabledwirelessdevices.WWWTheWorldWideWebisahypertext-basedsystemforfindingandaccessinginternetresources,anditisasetofprograms,standards,andprotocolsgoverningthewayinwhichmultimediafilesarecreatedanddisplayedontheInternet.Itcanprovideaccesstoavarietyofinternetresourcesfromthesameinterface,includingFTP.Gopher.TheWorldWideWebisadistributed,multimediaandhypertextsystem,andthusauniquemediumforcommunicationsandforpublishing.ThetermWWWisusedtodescribeaninterlinkedsystemofdocumentsinwhichausermayjumpfromonedocumenttoanotherinanonlinear,associativeway.Theabilitytojumpfromonedocumenttothenextismadepossibleviatheuseofhyperlinks.Byclickingonthehyperlink,theuserisimmediatelyconnectedtothedocumentspecifiedbythelink.MostdocumentsontheWebarewritteninHTML.HTTPstandsforHypertextTransferProtocol.ItisacommunicationprotocolthatfacilitatesthetransferofinformationontheInternet.Itisarequest-responseprotocolbetweenclientsandservers.Clientsarewebusersorwebbrowsers,whiletherespondingserverthatstoresorcreatestheresourcesrequestedisknownastheoriginserver.HTTPcanbeimplementedonanyoftheInternetprotocols.However,theTCPIPprotocolsuiteismostpopularlyused.AnHTTPclientestablishesaTCPconnectionwiththehost.Port80isthedefaultportusedfortheestablishmentofthisconnectionbetweentheclientandtheserverusingHTTP.Onreceivingtherequest,theserverreplieswithastatusline,amessageandtherequestedresource.SinceaprotocolissetofrulesandproceduresforcommunicationonanetworkandsinceHTTPisaprotocol-HTTPinitselfisasetofrulesandproceduresusedtocommunicateovertheWorldWideWeb.WorldWideWebConsortium(W3C)andtheInternetEngineeringTaskForce(IETF)coordinatedHTTPdevelopment.ItsinitialpurposewastoprovideawaytoretrieveandpublishHTMLdocuments.HTTPprotocolcomesunderapplicationlayer(Layer5)oftheTCP/IPmodel.HTTPclientsmakerequeststotheHTTPprotocolandtheconcernedHTTPserverhandlestheserequests.Theclientsmakingrequeststothewebserverarereferredtoasuseragents.Typicalclientsarewebbrowsers,searchenginespiders3,web-enabledapplications4,etc.ElectronicCommerceElectroniccommerce,commonlywrittenasE-commerce,isthetradingorfacilitationoftradinginproductsorservicesusingcomputernetworks,suchastheInternet.Electroniccommercemakesadvantageoftechnologiessuchasmobilecommerce,electronichindstransfer,supplychainmanagement,Internetmarketing,onlinetransactionprocessing,electronicdatainterchange(EDI),inventorymanagementsystems,andautomateddatacollectionsystems.ModemelectroniccommercetypicallyusestheWorldWideWebforatleastonepartofthetransaction'slifecycle,althoughitmayalsouseothertechnologiessuchasE-mail.E-commercebusinessesmayemploysomeorallofthefollowing:OnlineshoppingwebsitesforretailsalesdirecttoconsumersOnlineshoppingwebisaformofelectroniccommercewhichallowsconsumerstodirectlybuygoodsorservicesfromasellerovertheInternetusingawebbrowser.Alternativenamesare:e-web-store,e-shop.e-store,Internetshop,web-shop,web-store,onlinestore,onlinestorefrontandvirtualstore.Mobilecommerce(orM-commerce)describespurchasingfromanonlineretailer'smobileoptimizedonlinesiteorapp.Providingorparticipatinginonlinemarketplaces,whichprocessthird-partybusiness-to-consumerorconsumer-to-consumersales.Onlinemarketplaceisatypeofe-commercesitewhereproductorserviceinformationisprovidedbymultiplethirdparties,whereastransactionsareprocessedbythemarketplaceoperator.Onlinemarketplacesaretheprimarytypeofmultichannelecommerce.Inanonlinemarketplace,consumertransactionsareprocessedbythemarketplaceoperatorandthendeliveredandfulfilledbytheparticipatingretailersorwholesalers(oftencalleddropshipping).Othercapabilitiesmightincludeauctioning(forwardorreverse),catalogs,ordering,wantedadvertisement,tradingexchangefunctionalityandcapabilitieslikeRFQ,RFIorRFP.Task11.CloudComputingisatermthatconveystheuseofinformationtechnologyservices.2.Theresourceisprovidedonaservicebasis.3.CloudComputingisaparadigminwhichinformationispermanentlystoredinservers.4.Informationispermanentlystoredinserversontheinternetandcachedtemporarilyonclients.5.Innetworkdiagrams,resourcesaredepictedina“cloud”formation.6.Thelossofcontrolisseenasanegative,butitisgenerallyoutweighedbyseveralpositives.Task2資源利用resourceutilization控制的失去lossofcontrol較低的開銷lowercost負(fù)載均衡loadbalancing可靠性reliability可擴(kuò)展性scalability數(shù)據(jù)安全datasecurity敏感數(shù)據(jù)sensitivedateLesson7StructuredCablingandStandardizationOrganizationTask1閱讀和理解下文，并翻譯有下劃線地方的詞匯StandardOrganizationsRelatingtoIntegratedWiringTheInternationalOrganizationforStandardization(ISO)isaninternationalstandard-settingbodycomposedofrepresentativesfromvariousnationalstandardsorganizations.TheInternationalElectroTechnicalCommission(IEC)isanon-profit,non-governmentalinternationalstandardsorganizationthatpreparesandpublishesInternationalStandardsforallelectrical,electronicandrelatedtechnologies–collectivelyknownas"electrotechnology".TheInstituteofElectricalandElectronicsEngineers(IEEE)isaprofessionalassociationwithitscorporateofficeinNewYorkCityanditsoperationscenterinPiscataway,NewJersey.Itistheworld’slargestassociationoftechnicalprofessionalswithmorethan400,000membersinchaptersaroundtheworld.TheAmericanNationalStandardsInstitute(ANSI)isaprivatenon-profitorganizationthatoverseesthedevelopmentofvoluntaryconsensusstandardsforproducts,services,processes,systems,andpersonnelintheUnitedStates.TheTelecommunicationsIndustryAssociation(TIA)isaccreditedbytheAmericanNationalStandardsInstitute(ANSI)todevelopvoluntary,consensus-basedindustrystandardsforawidevarietyofInformationandCommunicationTechnologies(ICT)products,andcurrentlyrepresentsnearly400companies.TIA’sStandardsandTechnologyDepartmentoperatestwelveengineeringcommittees,whichdevelopguidelinesforprivateradioequipment,cellulartowers,dataterminals,satellites,telephoneterminalequipment,VoIPdevices,structuredcabling,datacenters,mobiledevicecommunications,multimediamulticast,vehiculartelematics（車輛遠(yuǎn)程信息處理）,healthcareICT,machinetomachinecommunications,andsmartutilitynetworks.TheElectronicIndustriesAlliancewasastandardsandtradeorganizationcomposedasanallianceoftradeassociationsforelectronicsmanufacturersintheUnitedStates.Theydevelopedstandardstoensuretheequipmentofdifferentmanufacturerswascompatibleandinterchangeable可互換的.CENELECisresponsibleforEuropeanstandardizationintheareaofelectricalengineering.TogetherwithETSI(EuropeanTelecommunicationsStandardsInstitute)andCEN(othertechnicalareas),itformstheEuropeansystemfortechnicalstandardization.TheEuropeanCommitteeforStandardizationisapublicstandardsorganizationwhosemissionistofostertheeconomyoftheEuropeanUnioninglobaltrading,thewelfareofEuropeancitizensandtheenvironmentbyprovidinganefficientinfrastructuretointerestedpartiesforthedevelopment,maintenanceanddistributionofcoherentsetsofstandardsandspecifications.Task2找出表示組織、協(xié)會(huì)、聯(lián)盟、委員會(huì)之類的詞organization、commission、institute、association、committee、allianceTaskWhyiswirelesscommunicationnecessary?Nowadaystherearepeoplewhoneedtobeon-lineallthetime.Somedevices,suchaswristwatch,havenointerfaceforanywire.Insomesituation,physicalwirescannotbelaidout.Lesson9NetworkingDevicesTask1將下列詞匯以適當(dāng)?shù)男问教顚懺谶m當(dāng)?shù)奈恢肎atewayscanperformallofthefunctionsofswitchesandroutersaswellasaccomplishingprotocolconversionatallsevenlayersoftheOSIReferenceModel.Generallyconsistingofsoftwareresidinginahostcomputerequivalentinprocessingpowertoamidrangeormainframe,gatewaytechnologyisexpensivebuthighlyfunctional.Protocolconversion,ratherthanencapsulation,canservetofullyconvertfromEthernettoTokenRingoranyotherstandardorproprietaryprotocol.Additionally,protocolconversioncanaddresshigherlayersoftheOSImodel,perhapsthroughLayer7,theApplicationLayer.Astheprocessofprotocolconversioniscomplex,gatewaystendtooperateratherslowlycomparedtoswitchesandrouters.Asaresult,theyimposeadditionallatencyonpackettrafficandmaycreatebottlenecksofcongestionduringperiodsofpeakusage.Inalargeandcomplexnetwork,routerstendtobepositionedattheedgesofthenetworkwheretheycanbeusedtofulladvantage.Therefore,theymakecomplexandtime-consumingdecisionsandinvokecomplexandtime-consumingprocessesonlywhererequired.Switchestendtobepositionedwithinthecoreofthenetwork,becausetheycanoperatewithgreaterspeed.Nowwecanconcludethatswitchcreatesseparatecollisiondomainsandroutercreatesseparatebroadcastdomains.Allportsofhubareonecollisiondomain.AcollisiondomainisdefinedasasingleCSMA/CDnetworksegmentinwhichtherewillbeacollisioniftwocomputersattachedtothesystembothtransmitatthesametime.Abroadcastdomainisalogicaldivisionofacomputernetwork,inwhichallnodescanreacheachotherbybroadcastatthedatalinklayer.(Figure9-5)Task2翻譯Inalargeandcomplexnetwork,routerstendtobepositionedattheedgesofthenetworkwheretheycanbeusedtofulfiladvantage.在一個(gè)大型而復(fù)雜的網(wǎng)絡(luò)中，路由器往往被放置在網(wǎng)絡(luò)的邊緣，在那里它們可以被充分利用。Nowwecanconcludethatswitchcreatesseparatecollisiondomainsandroutercreatesseparatebroadcastdomains.Allportsofhubareonecollisiondomain.現(xiàn)在我們可以得出這樣的結(jié)論:交換機(jī)創(chuàng)建了獨(dú)立的沖突域，路由器創(chuàng)建了獨(dú)立的廣播域。hub的所有端口都是一個(gè)沖突域。Lesson10NetworkSecurityTask1將下列詞匯以適當(dāng)形式填入下劃線所在空格ACLAnaccesscontrollistisessentiallyalistofconditionsthatcategorizepackets.Theycanbereallyhelpfulwhenyouneedtoexercisecontrolovernetworktraffic.Oneofthemostcommonandeasiesttounderstandtheusesofaccesslistsisfilteringunwantedpacketswhenimplementingsecuritypolicies.Therearetwomaintypesofaccesscontrollists:Standardaccesslists.TheseuseonlythesourceIPaddressinanIPpacketastheconditiontest.AlldecisionsaremadebasedonthesourceIPaddress.Thismeansthatstandardaccesslistsbasicallypermitordenyanentiresuiteofprotocols.Theydon’tdistinguishbetweenanyofthemanytypesofIPtrafficsuchasweb,Telnet,UDP,andsoon.Extendedaccesslists.Extendedaccesslistscanevaluatemanyoftheotherfieldsinthelayer3andlayer4headersofanIPpacket.TheycanevaluatesourceanddestinationIPaddresses,theprotocolfieldintheNetworklayerheader,andtheportnumberattheTransportlayerheader.Thisgivesextendedaccessliststheabilitytomakemuchmoregranulardecisionswhencontrollingtraffic.FirewallAfirewallisasystemdesignedtopreventunauthorizedaccesstoorfromaprivatenetwork.Youcanimplementafirewallineitherhardwareorsoftwareform,oracombinationofboth.FirewallspreventunauthorizedInternetusersfromaccessingprivatenetworksconnectedtotheInternet,especiallyintranets.Allmessagesenteringorleavingtheintranet(i.e.,thelocalnetworktowhichyouareconnected)mustpassthroughthefirewall,whichexamineseachmessageandblocksthosethatdonotmeetthespecifiedsecuritycriteria.Severaltypesoffirewalltechniquesexist:Packetfiltering:Thesystemexamineseachpacketenteringorleavingthenetworkandacceptsorrejectsitbasedonuser-definedrules.Packetfilteringisfairlyeffectiveandtransparenttousers,butitisdifficulttoconfigure.Inaddition,itissusceptibletoIPspoofing.Circuit-levelgatewayimplementation:ThisprocessappliessecuritymechanismswhenaTCPorUDPconnectionisestablished.Oncetheconnectionhasbeenmade,packetscanflowbetweenthehostswithoutfurtherchecking.Actingasaproxyserver:Aproxyserverisatypeofgatewaythathidesthetruenetworkaddressofthecomputer(s)connectingthroughit.AproxyserverconnectstotheInternet,makestherequestsforpages,connectionstoservers,etc.,andreceivesthedataonbehalfofthecomputer(s)behindit.Thefirewallcapabilitieslieinthefactthataproxycanbeconfiguredtoallowonlycertaintypesoftraffic(e.g.,HTTPfiles,orwebpages)topassthrough.Aproxyserverhasthepotentialdrawbackofslowingnetworkperformance,sinceithastoactivelyanalyzeandmanipulatetrafficpassingthroughit.IDSIntrusionDetectionSystems(IDSs)wereimplementedtopassivelymonitorthetrafficonanetwork.AnIDS-enableddevicecopiesthetrafficstream,andanalyzesthemonitoredtrafficratherthantheactualforwardedpackets.Itcomparesthecapturedtrafficstreamwithknownmalicioussignaturesinanofflinemannersimilartosoftwarethatchecksforviruses.ThisofflineIDSimplementationisreferredtoaspromiscuousmode.IPSAnIntrusionPreventionSystem(IPS)buildsuponIDStechnology.UnlikeIDS,anIPSdeviceisimplementedininlinemode.Thismeansthatallingressandegresstrafficmustflowthroughitforprocessing.AnIPSdoesnotallowpacketstoenterthetrustedsideofthenetworkwithoutfirstbeinganalyzed.Itcandetectandimmediatelyaddressanetworkproblemasrequired.ThebiggestdifferencebetweenIDSandIPSisthatanIPSrespondsimmediatelyanddoesnotallowanymalicioustraffictopass,whereasIDSmightallowmalicioustraffictopassbeforeresponding.IDSandIPStechnologiesdoshareseveralcharacteristics.IDSandIPStechnologiesarebothdeployedassensors.Task2翻譯Afirewallisasystemdesignedtopreventunauthorizedaccesstoorfromaprivatenetwork.防火墻是一種系統(tǒng)，旨在防止未經(jīng)授權(quán)的對(duì)私人網(wǎng)絡(luò)訪問或反之。Packetfilteringisfairlyeffectiveandtransparenttousers,butitisdifficulttoconfigure.Inaddition,itissusceptibletoIPspoofing.包過濾對(duì)用戶來說是相當(dāng)有效和透明的，但是很難配置。此外，它很容易受到IP欺騙。ThisofflineIDSimplementationisreferredtoaspromiscuousmode.這種脫機(jī)IDS的實(shí)施稱為混雜模式。Thismeansthatallingressandegresstrafficmustflowthroughitforprocessing.這意味著所有的輸入和輸出流星都必須通過它進(jìn)行處理。IDSandIPStechnologiesdoshareseveralcharacteristics.IDSandIPStechnologiesarebothdeployedassensors.IDS和IPS技術(shù)確實(shí)有幾個(gè)共同的特征。IDS和IPS技術(shù)都是作為監(jiān)測(cè)部署的。Taskl翻譯VPNsareoftenusedtoextendintranetsworldwidetodisseminateinformationandnewstoawideuserbase.VPN通常用于擴(kuò)展全球的內(nèi)部網(wǎng)，向廣泛的用戶群傳播信息和新聞。IPSecisoftenreferredtoasa“securityoverlay”becauseofitsuseasasecuritylayerforotherprotocols.IPSec通常被稱為“安全覆蓋層”，因?yàn)樗挥米髌渌麉f(xié)議的安全層。PPTPisoneofthemostwidelyusedVPNprotocolsbecauseofitsstraightforwardconfigurationandmaintenanceandalsobecauseitisincludedintheWindowsoperatingsystem.PPTP是最廣泛使用的VPN協(xié)議之一,因?yàn)樗呐渲煤途S護(hù)非常簡(jiǎn)單，而且它包含在Windows操作系統(tǒng)中。VPNtechnologyemployssophisticatedencryptiontoensuresecurityandpreventanyunintentionalinterceptionofdatabetweenprivatesites.VPN技術(shù)釆用了復(fù)雜的加密技術(shù)以確保安全性，防止在私有站點(diǎn)之間的數(shù)據(jù)被意外截取。TheuseoftheInternetasthemaincommunicationschannelbetweensitesisacosteffectivealternativetoexpensiveleasedprivatelines.使用英特網(wǎng)作為站點(diǎn)之間的主要通信渠道，相對(duì)昂貴的租用專用線路，是一種劃算的替代方案。Therelativeease,speed,andflexibilityofVPNprovisioningincomparisontoleasedlinesmakesVPNsanidealchoiceforcorporationswhorequireflexibility.與租用線路相比，VPN配置相對(duì)容易、快速和靈活，這使得VPN成為需要靈活性的企業(yè)的理想選擇。Task2private是有關(guān)所有權(quán)，confidential/secret是關(guān)于信息的公開范圍Task3PIN是什么的縮寫personalidentificationnumberTaskl翻譯Assuchitisnotoptimizedforuseasafileserverormediaserver.因此，它不是作為文件服務(wù)器或媒體服務(wù)器進(jìn)行的優(yōu)化。NetWare6.5SP8GeneralSupportendedin2010,withExtendedSupportuntiltheendof2015,andSelfSupportuntiltheendof2017.NetWare6.5SP8的一般支持在2010年結(jié)束，延伸支持到2015年底，自我支持到2017年底。Task2WhatdoWin2K8.Incstandforrespectively?Howtopronouncethem?“Win2K8"standsforWindowsServer2008".Incstandsfor“incorporated”. Task3翻譯即插即用 PnP（PlugandPlay） 熱插拔的hot-plugging BitLocker磁盤鎖（也可以不翻譯） Itanium-based 基于安騰的 IA-64英特爾安騰64位架構(gòu) Task4managerial和administrative在詞義上有什么區(qū)別？文中如何翻譯？都有“管理的”意思，但administrative的級(jí)別高。managerial側(cè)重于經(jīng)營(yíng)管理，administrative側(cè)重于行政管理。Task翻譯無(wú)線對(duì)講機(jī)walkie-talkie雙工duplex單工simplex半雙工half-duplex全雙工full-duplex校驗(yàn)位paritybit單播unicast廣播broadcast組播multicastLesson14CommunicationsProtocolsTask根據(jù)課文翻譯并解釋術(shù)語(yǔ)ISO國(guó)際標(biāo)準(zhǔn)化組織，InternationalOrganizationforStandardizationITU國(guó)際電信聯(lián)盟，InternationalTelecommunicationUnionIEEE電氣與電子工程師協(xié)會(huì)，InstituteofElectricalandElectronicEngineersIETF英特網(wǎng)工程任務(wù)組，InternetEngineeringTaskForceW3C萬(wàn)維網(wǎng)路聯(lián)盟，WorldWideWebConsortiumLessonCSMA/CDandIEEE802IEEE802IEEE802refersafamilyofIEEEstandardsdealinglocalareanetworksandmetropolitanareanetworks.MoretheIEEE802standardsarerestrictednetworkscarryingvariable-sizepackets.Bycontrast,cellrelaynetworksdatatransmittedshort,uniformlysizedunitscalledcells.Isochronousnetworks,wheredatatransmittedasasteadystreamofoctets,orgroupsofoctets,atregularintervals,arealsooutofthescopeofthisstandard.The802wassimplythenextfreenumberIEEEcouldassign,though“802”sometimesassociatedthedatethefirstmeetingwasheld—February1980.Theandprotocolsspecifiedthelower(DataLinkandPhysical)oftheseven-layerOSInetworkingreferencemodel.fact,IEEE802theOSIDataintosub-layersnamedLogicalLinkControlandMediaAccessControl(MAC),thatthelayerscanbelistedlikethis:?Data??SublayerMAC?PhysicalTheIEEE802familyofstandardsmaintainedbytheIEEE802StandardsCommittee(LMSC).ThewidelyusedstandardsfortheEthernetRing,LAN,BridgingBridgedLANs.AnindividualGroupprovidesthefocusforeacharea.IEEE802.3aworkinggroupandacollectionofIEEEstandardsproducedbytheworkinggroupdefiningthephysicallayeranddatalinklayersaccesscontrol(MAC)ofwiredEthernet.Thisgenerallyalocalareanetworktechnologywideareanetworkapplications.Physicalconnectionsaremadebetweennodesand/orinfrastructuredevices(hubs,switches,routers)byvarioustypesofcopperorfibercable.802.3atechnologythatsupportsIEEE802.1networkarchitecture.802.3alsodefineaccessmethodusingCSMA/CD.Introducedby1984,wasthenstandardizedprotocolIEEE802.5wasfairlysuccessful,particularlycorporateenvironments,butgraduallyeclipsedbythelaterversionsofEthernet.ringlocalareanetwork(LAN)technologyacommunicationsprotocolforlocalareanetworks.usesaspecialthree-byteframecalleda“token”thattravelsaroundalogical“ring”ofworkstationsorservers.Thistokenpassingachannelaccessmethodprovidingfairaccessforallstations,andeliminatingthecollisionsofcontention-basedaccessmethods.IEEEasetofaccesscontrol(MAC)andphysicallayer(PHY)specificationsforimplementingwirelesslocalareanetwork(WLAN)computercommunicationthe900MHzand2.4,3.6,5,60GHzfrequencybands.TheyarecreatedandmaintainedbytheInstituteofElectricalandElectronicsEngineers(IEEE)StandardsCommittee(IEEE802).Thebaseversionofthestandardwasreleased1997,hashadsubsequentamendments.Thestandardamendmentsprovidethebasisforwirelessnetworkproductsusingthebrand.Whileeachamendmentofficiallyrevokedwhenincorporatedthelatestversionofthestandard,thecorporatetendsmarkettherevisionsbecausetheyconciselydenotecapabilitiesoftheirproducts.Asaresult,themarketplace,eachrevisiontendsbecomeownstandard.Lesson16IPandDNSTask1翻譯Aspecificnode’sdomainnameisthelist