操作系统原理绪论(英文课件)

IntroductiontoOperatingSystemPrinciples(EngliCATALOGUE目录IntroductionTypesofOperatingSystemsOperatingSystemStructureBasicFunctionsofOperatingSystemSecurityinOperatingSystemFutureTrendsinOperatingSystem01IntroductionAnoperatingsystemisasoftwarethatmanagesandcontrolscomputerhardwareresources,suchasCPU,memory,anddevices,andprovidesaconvenientinterfaceforusersandapplicationprograms.Theoperatingsystemactsasanintermediarybetweentheuserandthecomputerhardware,allowinguserstointeractwiththecomputermoreconvenientlyandefficiently.Itisthecorecomponentofacomputersystem,responsibleforresourceallocation,systemsecurity,andsystemstability.DefinitionofOperatingSystemImportanceofOperatingSystemProvidesaconvenientinterfaceforusers:Theoperatingsystemprovidesvarioususerinterfaces,suchascommandlines,graphicaluserinterfaces,andtouchscreens,toallowuserstointeractwiththecomputermoreconveniently.Implementsresourcemanagement:Theoperatingsystemmanagescomputerhardwareresources,suchasCPU,memory,anddevices,toensurethattheyareallocatedandusedefficiently.Ensuressystemsecurity:Theoperatingsystemprovidessecuritymechanismstoprotectsystemfiles,preventunauthorizedaccesstoresources,andpreventmalicioussoftwarefromattackingthesystem.Improvessystemstability:Theoperatingsystemcandetectandcorrecterrorsinthesystemtoensurethestabilityofthesystem.EvolutionofOperatingSystemThefirstgenerationofcomputersdidnothaveoperatingsystems.Usershadtowriteprogramsdirectlyinmachinelanguagetocontrolthecomputer.Inthesecondgenerationofcomputers,simpleoperatingsystemsweredevelopedtomanagecomputerresourcesandprovidebasicservicesforusersandapplicationprograms.Withthedevelopmentoftechnology,moreadvancedoperatingsystemsweregraduallydevelopedinthethirdgenerationofcomputers.Theseoperatingsystemshadmorepowerfulfunctionsandprovidedmoreconvenientinterfacesforusers.Nowadays,withthepopularizationofpersonalcomputersandthedevelopmentofcloudcomputing,operatingsystemshavebecomemorediverseandflexible.Theynotonlymanagelocalresources,butalsocanintegrateandmanagedistributedresourcesacrossthenetwork.02TypesofOperatingSystemsBatchProcessingOperatingSystemsaredesignedtohandleagroupofjobsinaqueueandexecutethemonebyone.BatchProcessingOperatingSystemsarelesscomplexandhavefewerresourcescomparedtoothertypesofoperatingsystems.Theyaresuitablefornon-interactiveprocessingandareusedinsituationswhereprocessingspeedisnotcritical.BatchProcessingOperatingSystemsRealTimeOperatingSystems01RealTimeOperatingSystemsaredesignedtohandletime-criticaltasksandprovideguaranteedresponsetimes.02Theyareusedinembeddedsystems,avionics,andothercriticalapplicationswheretimelyexecutionisessential.RealTimeOperatingSystemshavefeatureslikefixedscheduling,priority-basedtaskexecution,andlowinterruptlatency.03NetworkOperatingSystemsaremorecomplexandhavemoreresourcescomparedtoothertypesofoperatingsystems.NetworkOperatingSystemsaredesignedtomanagenetworkresourcesandprovidenetworkservicestomultipleusers.Theyprovidefeatureslikefilesharing,printingservices,andaccesstonetworkresourcesusingacommonprotocollikeTCP/IP.NetworkOperatingSystems010203MobileOperatingSystemsaredesignedtopowersmartphones,tablets,andothermobiledevices.Theyprovidefeaturesliketouchscreensupport,multi-tasking,andaccesstomobileapplications.MobileOperatingSystemshaveauser-friendlyinterfaceandaredesignedforportabilityandbatteryefficiency.MobileOperatingSystems03OperatingSystemStructure输入标题02010403KernelKernelisthecoreoftheoperatingsystemandmanagesthesystemresources.Itrunsinprivilegedmodeandhasdirectaccesstothesystemhardware.Thekernelisresponsibleforensuringthesecurityandstabilityofthesystem.Itprovidesessentialservicestothesystemprogramsandutilities,suchasmemorymanagement,processscheduling,anddevicedrivers.SystemPrograms01Systemprogramsarehigh-levelsoftwarethatperformsspecifictasksonbehalfofusersorotherprograms.02Theseprogramsincludecompilers,interpreters,debuggers,andtexteditors.03Theyaretypicallywritteninahigh-levellanguageandrunontopofthekernel.04Systemprogramsprovideconvenientinterfacesforuserstointeractwiththeoperatingsystem.01Somecommonexamplesincludefilecompressiontools,diskformattingtools,andsystemmonitoringtools.Utilitiesaretypicallystandaloneprogramsthatcanbelaunchedfromthecommandlineordesktopenvironment.Theyprovideaconvenientwayforuserstoperformcommontaskswithouthavingtousecomplexsystemprograms.Utilitiesaresmalltoolsthatprovidespecificfunctionstohelpusersmanagetheirfiles,disks,andotherresources.020304UtilitiesItincludesgraphicaluserinterfaces(GUI)andcommandlineinterfaces(CLI).AGUIprovidesavisualinterfacewithwindows,icons,menus,anddialogboxes.Theuserinterfacemustbeeasytouse,intuitive,andresponsivetouserinput.ACLIallowsuserstoentercommandstoperformoperationsonthesystem.Theuserinterfaceisthemeansbywhichusersinteractwiththeoperatingsystem.UserInterface04BasicFunctionsofOperatingSystemProcessCreationTheOScreatesandmanagesprocesses,whichareinstancesofprogramsthatarecurrentlyexecuting.TheOSassignsCPUtimetoprocesses,determiningwhichprocessrunsandwhen.TheOSensuresthatprocessesaccesssharedresourcesinacoordinatedmannertoavoidconflicts.Whenaprocesscompletesorneedstobestopped,theOShandlesitsterminationandreleasesitsresources.ProcessSchedulingProcessSynchronizationProcessTerminationProcessManagementTheOSimplementsavirtualmemorysystemthatprovideseachprocesswithitsownprivatememoryspace.VirtualMemoryWhenaprocessnolongerneedsaportionofmemory,theOSreclaimsitforreusebyotherprocesses.MemoryReclamationTheOSdynamicallyallocatesmemorytoprocessesbasedontheirneedsandavailablememoryresources.MemoryAllocationTheOSensuresthateachprocesscanonlyaccessitsownmemoryspacetopreventunauthorizedaccess.MemoryProtectionMemoryManagementFileStorageTheOSmanagesthestorageoffilesonsecondarystoragedevices,suchasharddisks.FileAccessControlTheOSenforcesaccesspermissionstofiles,determiningwhichusersorprocessescanread,write,orexecutethem.FileSystemStructureTheOSorganizesfilesintodirectoriesandprovidesahierarchicalstructureforfilestorageandretrieval.FileSharingTheOSenablesmultipleusersandprocessestoaccessthesamefilesimultaneously,providingconcurrentfileaccess.FileManagementTheOSidentifiesandregistersalldevicesconnectedtothesystem,suchasprinters,mice,andkeyboards.DeviceRegistrationTheOSmanagesdevicedrivers,whicharesoftwareinterfacesthatenabletheOStocommunicatewithdevices.DeviceDriverManagementTheOSenforcesaccesspermissionsfordevices,determiningwhichusersorprocessescanusethem.DeviceAccessControlTheOSallocatesdeviceresources,suchasdatatransferratesorbuffersizes,tooptimizedeviceperformance.DeviceResourceAllocationDeviceManagement05SecurityinOperatingSystemVirusesTypes:蠕虫病毒、宏病毒、文件病毒、启动区病毒、玩笑病毒、破坏性程序病毒、巨集病毒、木马病毒。Effects:破坏文件、干扰操作、降低系统性能、窃取用户信息。VirusesandMalwarePrevention:Keepinganti-virussoftwareuptodate,usingsecureemailclients,andnotopeningemailfromunknownsenders.VirusesandMalwareMalwareEffects:偷窥用户隐私、破坏系统设置、干扰用户操作。Prevention:Usingreputableanti-malwaresoftware,updatingsoftwareregularly,andbeingcarefulwhendownloadingfilesfromtheinternet.Types:间谍软件、广告软件、木马、蠕虫。VirusesandMalware物理层漏洞、网络层漏洞、数据链路层漏洞和应用层漏洞。Types非法访问、数据泄露、拒绝服务攻击。EffectsRegularlyupdatingandpatchingoperatingsystems,usingstrongpasswords,andimplementingnetworksecuritymeasures.PreventionSystemVulnerabilities03Purpose:Toprotectsensitiveinformationfromunauthorizedaccess.01Encryption02Types:对称加密和公钥加密。EncryptionandDecryptionTechniquesMethods:AES,DES,RSA.EncryptionandDecryptionTechniques123DecryptionMethods:Inversekeypairsfordecryptioninpublickeycryptography.Difficulties:Cryptanalysistechniquescanbeusedtodecryptencryptedmessages.EncryptionandDecryptionTechniques06FutureTrendsinOperatingSystemCloudComputingOperatingSystemsCloudcomputingOSesaredesignedtohandlethedynamicnatureofcloudcomputing,whereresourcesaresharedandcanbescaledupordownbasedondemand.Theyprovideavirtualizedenvironmentthatallowsuserstoaccesscomputingresourcesseamlesslyfromanywhereatanytime,usinganydevice.CloudOSesareresponsibleformanagingtheallocationanddeallocationofresources,ensuringhighavailabilityandfaulttolerance,andprovidingsecurityandisolationbetweendifferentusersandtheirrespectiveresources.01Distri