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CSC1100 - Chapter06 - Operating System & Utility Programs
 

CSC1100 - Chapter06 - Operating System & Utility Programs

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စက်လည်ပတ်စနစ်နှင့်အသံုးချပရိုဂရမ်များ

စက်လည်ပတ်စနစ်နှင့်အသံုးချပရိုဂရမ်များ

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    CSC1100 - Chapter06 - Operating System & Utility Programs CSC1100 - Chapter06 - Operating System & Utility Programs Presentation Transcript

    • Discovering Computers 2008Chapter 6Chapter 6Chapter 6Chapter 6Chapter 6Chapter 6Chapter 6Chapter 6OperatingOperatingOperatingOperatingSystems andSystems andSystems andSystems andUtility ProgramsUtility ProgramsUtility ProgramsUtility Programs
    • 2Chapter 6 ObjectivesChapter 6 ObjectivesChapter 6 ObjectivesChapter 6 ObjectivesIdentify the types of system softwareIdentify the types of system softwareSummarize the startup processon a personal computerSummarize the startup processon a personal computerSummarize the features of severalstand-alone operating systemsSummarize the features of severalstand-alone operating systemsIdentify various network operating systemsIdentify various network operating systemsDiscuss ways that some operatingsystems help administrators control anetwork and administer securityDiscuss ways that some operatingsystems help administrators control anetwork and administer securityExplain the purpose of the utilitiesincluded with most operating systemsExplain the purpose of the utilitiesincluded with most operating systemsIdentify devices that use severalembedded operating systemsIdentify devices that use severalembedded operating systemsExplain the purpose of severalstand-alone utility programsExplain the purpose of severalstand-alone utility programsDescribe the functions of an operating systemDescribe the functions of an operating system
    • 3System SoftwareSystem SoftwareSystem SoftwareSystem SoftwareWhat is system software?Operating system (OS)Operating system (OS)Programs that controlPrograms that controloror maintain operationmaintain operationof computer & its devicesof computer & its devicesTwo types areTwo types areoperating systemsoperating systemsand utility programsand utility programsOperating system (OS)Operating system (OS)(sometimes called the(sometimes called the platformplatform))a set ofa set of programsprograms containingcontaininginstructionsinstructions thatthat coordinatescoordinatesall activitiesall activities among computeramong computerhardware resourceshardware resources When purchase aPC, it usually hassystem software onits h/d
    • 4Operating SystemsOperating SystemsOperating SystemsOperating SystemsWhat are the functions of an operating system?Most OSs perform similar functions:start the computer provide a user interfacemanage programsadministersecuritymanagememorymonitorperformancecontrol anetworkprovide filemanagement andother utilitiesestablish anInternet connectionschedule jobs andconfigure devices
    • 5Operating SystemsOperating SystemsOperating SystemsOperating SystemsMostly OS installed & resides incomputer h/dHandheld computers & mobile devices– OS resides on a ROM chipDifferent size computers use differentDifferent size computers use differentoperating systems.Some computers can run multiple OSWhen purchasing an applicationsoftware, user must ensure that it workswith the OS installed in the computer
    • 6Operating SystemsOperating SystemsOperating SystemsOperating SystemsWhat is a cross-platform application?ApplicationRuns the same on multiple operating systemsOperating System/Platform AOperating System/Platform BOperating System/Platform COperating System/Platform DApplication
    • 7Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions1) Starting a ComputerWhat is booting?Cold boot Turning oncomputer that has beenpowered offWarm boot RestartingProcess of starting or restarting a computerWarm boot Restartingcomputer that is powered onDoes not save any unsaved workInstallation/upgrade new swNo response, push reset buttonStill no response, push powerbutton – does not properly closerunning processes & programs
    • 8BootingBootingBootingBootingEach time boot computer,the kernel and other frequently used OS instructionsare loaded/copied into computer’s memory (RAM).Kernelthe core of an OS that managesmemory & devices, maintains the computer’s clock,memory & devices, maintains the computer’s clock,starts application, andassigns the computer’s resources (devices, programs,data & information)is memory resident – it remains in memory whilecomputer is runningother parts of OS are nonresident – these instructionsremain on h/d until they are needed.
    • 9Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System FunctionsHow does a personal computer boot up?Step 1. Powersupply sends signalto components insystem unitStep 4. Results of POST arecompared with data in CMOS chipStep 5. BIOS looks for systemfiles on a USB flash drive orStep 2. Processoraccesses BIOS tostart computerStep 3. BIOS runstests, called thePOST, to checkcomponents such asmouse, keyboard,and adapter cardsfiles on a USB flash drive orCD/DVD drive, and then drive C(hard disk)Step 6. Kernel (core) ofoperating system loads into RAMStep 7. Operating system loadsconfiguration information anddisplays desktop on screen
    • 10Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System FunctionsWhat is a boot disk?Contains system files that will start computer whencomputer cannot bootContains few system files that will start the computerAlso called recovery diskUsed when h/d becomes damaged & computer cannot bootUsed when h/d becomes damaged & computer cannot bootfrom h/dBoot disk in CD form usually included when purchasing acomputerWindows Vista installation disk itself is a boot disk
    • 11Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions2) Providing a User InterfaceWhat is a user interface?Controls how you enter data and instructions and howinformation displays on screenCommand-line interface: for advanced usersto configure devices, troubleshoot networkconnections,… using command language
    • 12Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System FunctionsWhat is a graphical user interface (GUI)?User interacts with menus andvisual images such as buttonsand other graphical objectsBasic InterfaceWindows Aero InterfaceWindows Aero Interface
    • 13Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions3) Managing ProgramsWhat is single user/ multitasking?Working on two or moreprograms that reside inmemory at same timePrograms can runconcurrentlyForeground contains programyou are usingBackground contains programsthat are running but are notin useconcurrently
    • 14Single user/single tasking OS:One user runs one program at a timeUsed by PDAs, smart phones & other smallcomputing devices
    • 15Enables two orOperating System FunctionsOperating System FunctionsOperating System FunctionsOperating System FunctionsWhat are other program management features ofoperating systems?Can support twoPrevent a processfrom monopolizingthe computerHas duplicatecomponents such asprocessors, memory,and disk drivesEnables two ormore users torun programssimultaneouslyContinues tooperate when oneof its componentsfailsCan support twoor more processorsrunning programsat same timeresourcesOS interrupts a prg which isexecuting & passes control toanother prg waiting to beexecuted.ADV: OS regains control is oneprg stops operating properly
    • 16Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions4) Managing MemoryWhat is memory management?Optimizing use of random access memory (RAM)With virtual memory (VM), portion of hard disk isallocated to function as RAM
    • 17Virtual MemoryVirtual MemoryVirtual MemoryVirtual MemoryIf multiple program running simultaneously – it is possibleto run out of RAME.g.: (OS) 512MB + (antivirus prg) 256MB + (Webbrowser) 128MB + (buss. sw. suite) 512MB + (photobrowser) 128MB + (buss. sw. suite) 512MB + (photoediting prg) 256MB = 1664MB or RAM required.If computer has only 512MB of RAM (physical RAM), OSneed virtual memory to solve this problemOS allocates a portion of a storage medium (h/d – swapfile) to function as additional RAM (computer may slowdown)
    • 18Virtual MemoryVirtual MemoryVirtual MemoryVirtual MemorySwap file: h/d area used for virtual memory (swap itemsbtw memory & storage)Page = the amount of data & prg instructions that canswap at a timePaging = technique of swapping items btw memory &Paging = technique of swapping items btw memory &storage – time consumingTrashing = happens when OS spends much time forpaging instead of executing application software (whenweb browser stop responding & h/d LED blinks – OS isthrashing)
    • 19
    • 20Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions5) Scheduling JobsHow does an operating system schedule jobs?SendingSendinginformationinformationReceiving dataReceiving dataAdjusts schedulebased onjob’s priorityTransferring itemsTransferring itemsbetween storagebetween storageand memoryand memoryinformationinformationto output deviceto output deviceProcessingProcessinginstructionsinstructionsReceiving dataReceiving datafrom input devicefrom input deviceAA jobjob isis operationoperationthe processor managesthe processor managesA segmentof memory/storage– items placed while waitingto be transferred frominput or tooutput devicebufferbuffer
    • 21Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System FunctionsWhat is spooling?(OS) Sending print jobs to buffer instead ofdirectly to printerPrint jobs line up in queue
    • 22Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions6) Configuring DevicesWhat is a device driver?DeviceDeviceProgram thatProgram thattells operating systemtells operating systemWithWith Plug and PlayPlug and Play,,operating systemoperating systemDeviceDeviceDriverDrivertells operating systemtells operating systemhow to communicatehow to communicatewith devicewith deviceoperating systemoperating systemautomaticallyautomaticallyconfigures newconfigures newdevices as you installdevices as you installthemthemAlso calledAlso called driverdriver
    • 23Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System FunctionsHow do you install a device driver?Step 1. Open Control Step 2. Click the HardwareStep 3. Click theScanners and CamerasStep 4. Click the AddDevice button to startStep 1. Open ControlPanel window. Point toHardware and Sound link.Step 2. Click the Hardwareand Sound link to displaythe Hardware and Soundoptions. Point to theScanners and Cameras link.Scanners and Cameraslink to display theScanners and Camerasdialog box. Point tothe Add Device button.Device button to startthe Scanner andCamera InstallationWizard. Point to theNext button.Step 5. Click the Next button to proceed with the wizard.Select the correct manufacturer and model of scanner orcamera. Follow the on-screen instructions to completeinstallation of the necessary driver files for the selecteddevice.
    • 24Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions7) Establishing an Internet ConnectionHow do you establish an Internet connection?Windows Vista includesConnect to a networkwizardGuides user through settingup connection betweenup connection betweencomputer and Internetservice provider
    • 25Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions8) Monitoring PerformanceHow does an operating system monitor performance?Provides program, called performance monitor,that assesses and reports information aboutsystem resourcesand devices
    • 26Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions9) Controlling NetworkWhat is a network operating system?Allows users to share resources on anetworkAdministers securityby establishing username and password forname and password foreach user
    • 27Operating System FunctionsOperating System FunctionsOperating System FunctionsOperating System Functions10) Administering SecurityNetwork administrators use network OS to establishpermissions to the users to be able to access resourcesUse account (user name/user ID & password) – enables auser to access or log on to a computer or a networkThe OS records successful & unsuccessful logon attemptsin a file – monitor computer usagein a file – monitor computer usageEncryption – the process of encoding data& informationinto an unreadable formEspecially as it travels over the network to preventunauthorized users from reading the dataEncrypted items automatically decrypted into readableform when an authorized reader attempts to read them
    • 28Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is a utility program?System software that performsmaintenance-type tasksAlso calledutility
    • 29Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is a file manager?Performs functions related to file managementImage viewer displays,copies, & printscontents of graphicsfilefileUser can see imagewithout having toopen them in paint/image editingprogramWindow VistaWindow Vista –– Window Photo GalleryWindow Photo Gallery
    • 30Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is a personal firewall?Detects and protects a personal computer fromunauthorized intrusionsEspecially for broadband Internet connectionConstantly monitors all transmissions to &from a computerfrom a computerWindows Vistaautomatically enables thebuilt-in personal firewallupon installationSomeone who triesto access a computeror network illegallyhackerhacker
    • 31Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is an uninstaller?In Windows Vista,In Windows Vista,uninstaller is available throughuninstaller is available throughthe Uninstall a program commandthe Uninstall a program commandin thein the Control PanelControl PanelRemoves aRemoves aprogram andprogram andall associated filesall associated files
    • 32Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is a disk scanner?Searches for and removesunnecessary files such astemporary filesWindows Vista includesDisk CleanupDisk Cleanup
    • 33Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is a disk defragmenter?Reorganizes files and unused space on hard disk soprograms run faster
    • 34Disk DefragmenterDisk DefragmenterDisk DefragmenterDisk DefragmenterWhen OS stores a file on a disk it places the file in theWhen OS stores a file on a disk it places the file in thefirst available sector on diskIt attempts to place it in contiguous sectors, but notalways possibleFile contents are scattered across two or more non-contiguous sectors – file is fragmented –Fragmentation slows down disk access & overallcomputer performance
    • 35Disk DefragmenterDisk DefragmenterDisk DefragmenterDisk DefragmenterDefragmenting the disk, or reorganizing it so the filesare stored in contiguous sectors, solve this problem
    • 36Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is a diagnostic utility?Compiles technical information about hardware andsome softwarePrepares report outlining problemsInformation in the report assists technical supportstaff in remedying any problemsstaff in remedying any problemsWindows Vista includes Problem Reports andSolutionsDiagnoses problems as well as suggests courses ofaction
    • 37Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is a backup utility?Copies selected files or entire hard disk ontoanother storage mediumMost compress filesduring backup torequire less storagerequire less storagespace
    • 38Operating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsOperating System Utility ProgramsWhat is a screen saver?Causes monitor’s screen to display movingimage or blank screen if there is no activityfor a specified timeTo secure computer,user configures screenuser configures screensaver to requirepassword todeactivate
    • 39Device-dependentRuns only onTypes of Operating SystemsTypes of Operating SystemsTypes of Operating SystemsTypes of Operating SystemsWhat are some characteristics of operating systems?ProprietarysoftwarePrivately owned andlimited to specificDevice-independentRuns on manyRuns only onspecific type ofcomputerDownwardcompatibleWorks with applicationsoftware written forearlier version of OSUpwardcompatibleRuns on new versionsof OSlimited to specificvendor/computermodelRuns on manymanufacturers’computers
    • 40Types of Operating SystemsTypes of Operating SystemsTypes of Operating SystemsTypes of Operating SystemsWhat are three categories of operating systems?EEMMBBEENNEETTWWS T A N DS T A N D –– A L O N EA L O N EDDDDEEDDWWOORRKKWindows XP, Vista, Mac OS X, UNIX & Linux
    • 41StandStandStandStand----Alone Operating SystemsAlone Operating SystemsAlone Operating SystemsAlone Operating SystemsHow do Windowsversions compare?Windows Version Year ReleasedWindows 3.x 1990Windows NT 3.1 1993Windows 95 1995Windows NT Workstation 4.0 1996Windows 98 1998Windows Millennium Edition 2000Windows 2000 Professional 2000Windows XP 2001Windows XP SP2 2004Windows Vista 2006
    • 42Fast, reliable Windows operating systemStandStandStandStand----Alone Operating SystemsAlone Operating SystemsAlone Operating SystemsAlone Operating SystemsWhat is Windows XP?Available in fiveeditions:Home Edition,Professional Edition,Professional Edition,Tablet PC Edition,Media Center Edition,and 64-bit EditionFor power usersworking withworkstations that use64-bit processors
    • 43Successor to Windows XP, containing a newinterface and new / enhanced featuresStandStandStandStand----Alone Operating SystemsAlone Operating SystemsAlone Operating SystemsAlone Operating SystemsWhat is Windows Vista?Available in severaleditions, grouped intoHome and BusinessHome and BusinesscategoriesMore reliable,efficient, quickerapplication starter,better security,enhanced searching,…512 MB RAMfor Vista Basic,1GB RAM &128MB video/graphic memoryfor V Premium, Ultimate,Business, Enterprise
    • 44Windows Vista FeaturesReliability and PerformanceSecurityInformation ManagementStandStandStandStand----Alone Operating SystemsAlone Operating SystemsAlone Operating SystemsAlone Operating SystemsWhat are some features of Windows Vista?Information ManagementAppearance and NavigationCommunications and the Internet
    • 45StandStandStandStand----Alone Operating SystemsAlone Operating SystemsAlone Operating SystemsAlone Operating SystemsWhat is Mac OS X?Available only for computersmanufactured by AppleMacintosh operatingsystem has beenmodel for most GUIsmodel for most GUIsHas large photo-quality icons,built-in networking support,enhanced speech recognition& multimedia capabilities
    • 46StandStandStandStand----Alone Operating SystemsAlone Operating SystemsAlone Operating SystemsAlone Operating SystemsWhat is UNIX?Created in early 1970sUsed by power users because of its flexibilityand powerSuitable for PC & workstationsMost versions offer GUI,Most versions offer GUI,others in command-lineAvailable for computersof all sizes
    • 47StandStandStandStand----Alone Operating SystemsAlone Operating SystemsAlone Operating SystemsAlone Operating SystemsWhat is Linux?Popular, free, multitasking UNIX-type operating systemOpen-source softwarecode is available to publicCode provided for usage, modification &redistributionredistributionHas no restrictions from copyright holderAvailable in GUI & command-line interfacesInclude many free prg. languages & utility programsFamous GUIs: GNOME & KDEBoth a stand-alone & a network operating system
    • 48LinuxLinuxLinuxLinux2 ADV:users share OS softwareimprovements with othersCustomers can personalizethe software to meet theirneedsRed Hat provides a version of Linuxcalled Red Hat Enterprise Linux.needsBootable OS:Live CD or Live USB
    • 49Network Operating SystemsNetwork Operating SystemsNetwork Operating SystemsNetwork Operating SystemsWhat are examples of networkoperating systems?NetWareNetWareDesigned forDesigned forclient/serverclient/servernetworksnetworksWindowsWindows UNIX / LinuxUNIX / LinuxWindowsWindowsServer 2003Server 2003Upgrade to WindowsUpgrade to Windows2000 Server2000 ServerUNIX / LinuxUNIX / LinuxMultiMulti--purposepurposeOSOSSolarisSolarisVersion ofVersion of UNIXUNIXdeveloped by Sundeveloped by SunMicrosystemsMicrosystemsSpecifically forSpecifically foree--commercecommerceapplicationsapplications
    • 50Embedded Operating SystemsEmbedded Operating SystemsEmbedded Operating SystemsEmbedded Operating SystemsWhat is an embedded operating system?Found on most PDAs andsmall devicesWindows CE isscaled-down version ofWindowsWindows
    • 51Embedded Operating SystemsEmbedded Operating SystemsEmbedded Operating SystemsEmbedded Operating SystemsWhat are three operating systems for mobile devices?Windows Mobile for PDAs, called Pocket PC & smartphonesPalm OS for PDAs & smart phonesBlackberry for handheld devices supplied by RIM(Research in Motion)(Research in Motion)
    • 52Embedded Operating SystemsEmbedded Operating SystemsEmbedded Operating SystemsEmbedded Operating SystemsWhat is Embedded Linux?Scaled-down Linux operating systemdesigned for PDAs, smart phones,smart watches, set-top boxes,Internet telephones, and otherdevicesdevicesOffers many PIM functions
    • 53Embedded Operating SystemsEmbedded Operating SystemsEmbedded Operating SystemsEmbedded Operating SystemsWhat is Symbian OS?Open-source, multitasking operating systemdesigned for smart phonesMake telephone calls,save appointments,browse Web, sendbrowse Web, sendand receive e-mailand faxes, and more
    • 54StandStandStandStand----Alone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsWhat is a virus?Potentially damaging computer programAffects computer without user’s knowledge• An unusual message or image is displayed on thecomputer screenSIGNS OFSIGNS OFVIRUSVIRUSINFECTIONINFECTIONcomputer screen• An unusual sound or music plays randomly• The available memory is less than what should beavailable• A program or file suddenly is missing• An unknown program or file mysteriously appears• The size of a file changes without explanation• A file becomes corrupted• A program or file does not work properly• System properties change
    • 55StandStandStandStand----Alone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsWhat is an antivirus program?Identifies and removes viruses in memory, storagemedia, and incoming filesMust be updated frequently
    • 56StandStandStandStand----Alone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsWhat is spyware?Program placed on a computer without the user’sknowledge that secretly collects information about theuserOften enters a computer as a result of a user installinga new programa new programA spyware remover is a program that detects anddeletes spyware
    • 57StandStandStandStand----Alone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsWhat are internet filters?Programs that remove or block certain items frombeing displayedFiltering prg Restrict access toPop-upBlockersAnti-SpamProgramsWebFiltersremoves spam bfrreaching inboxRestrict access tocertain materialson Web, that usescertain words orphrasesStops pop-up advertisements appearing in new windowin the foreground of a Web page displayed in browser
    • 58StandStandStandStand----Alone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsWhat is a file compression utility?Shrinks size of files to free up room and improveperformanceCompressed files are sometimes called zipped filesTwo popular utilities:PKZIP and WinZipPKZIP and WinZip
    • 59StandStandStandStand----Alone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsWhat is a media player?Allows you to viewimages and animation,listen to audio, andwatch video files onyour computeryour computer
    • 60StandStandStandStand----Alone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsWhat is CD/DVD burning software?Writes text, graphics,audio, and video files toa recordable orrewriteable CD or DVD
    • 61StandStandStandStand----Alone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsAlone Utility ProgramsWhat is a personal computer maintenance utility?Identifies and fixes operating system problems anddisk problemsSome continuously monitorcomputer to identify problemsbefore they occur & evenbefore they occur & evenfix them immediatelyNote: diagnostic utility does notrepair the problems it found
    • 62Summary of Operating Systems and Utility ProgramsSummary of Operating Systems and Utility ProgramsSummary of Operating Systems and Utility ProgramsSummary of Operating Systems and Utility ProgramsDefine an operating systemDefine an operating systemDiscuss the functions common tomost operating systemsDiscuss the functions common tomost operating systemsDiscuss a variety of stand-aloneoperating systems, network operating systems,and embedded operating systemsDiscuss a variety of stand-aloneoperating systems, network operating systems,and embedded operating systemsChapter 6 Completemost operating systemsmost operating systemsIntroduce several utility programs commonlyfound in operating systemsIntroduce several utility programs commonlyfound in operating systemsDescribe several stand-aloneutility programsDescribe several stand-aloneutility programs