Review For FinalComputer HardwareThe Core Computer ComponentsOutput DevicesPrintersI/O devices or Secondary StorageSlide 7Processing subsystemCentral Processing UnitCPU speedPrimary StorageSummary QuestionsSoftware TechnologySlide 14Main Types of SoftwareSlide 16Operating Systems (OS)Managing Memory: MultiprogrammingManaging Memory: Virtual MemorySlide 20Network TechnologyComputer NetworkTransmission MediaTransmission Media (Continued)Wireless MediaNetwork TopologiesNetwork ArchitectureProtocolsTCP/IPEthernetToken RingTransmitting Data in a NetworkSlide 33IS For Business IntegrationDevelopment of ISSecurity and privacy1Review For Final© Abdou Illia(Fall 2007)2Computer Hardware3The Core Computer ComponentsThree subsystems in a computer system:1. Input subsystem2. Processing subsystem3. Output subsystem4Output DevicesMonitorsCathode ray tube (CRTs)Liquid crystal displays (LCDs)Quality of displayResolution in pixels (e.g. 640 x 480)Dot pitch in millimeters (.26 to .28)Active-Matrix vs. Passive-Matrix displayTouch screensInput and output via display deviceMonitor size Common resolution15 inches 640 x 48017 inches 800 x 600 or 1024 x 76819 inches 1024 x 768 or 1280 x 10245PrintersSpeed and resolutionPages per minute (PPM)Dots per inch (DPI)Number of ink dots to fill a square inchHigher DPI = greater page clarityImpact printersCreate image by striking paper and ribbonDot-matrix printers = most common impact printersNon-impact printersCreate image by spraying or rolling ink on the page6I/O devices or Secondary StorageNonvolatile storage of digital dataMagnetic or opticalMagnetic storage (Floppy disk, Magnetic tape, Zip disk, Hard disk)Sequential access (tape) or direct access (HDD)Hard disk drivesTwo main standards:IDE (Integrated Drive Electronics) aka ATA (AT Attachment)SCSI (Small Computer System Interface)SCSI allows disk fault-tolerance through RAID – Redundant Array of Inexpensive DisksDisk speed:Transfer rate in MBps (Megabytes per second)Average Read Time (in milliseconds or ms)Platter rotation speed in RPM (5400/7200/10,000/15,000)78Processing subsystemTwo major componentsCPU (Central Processing Unit) or Processor(s)Primary Storage:Random Access Memory (RAM)Read Only Memory (ROM)CPUPrimary StorageBusses that transfer data9Central Processing UnitClock: generate time that synchronize other componentsICU: Fetches instructions from RAMALU: Execute instructions (arithmetic & logic operations)Registers: Store control information, data, intermediate resultsProcessorClockInstruction Control UnitArithmetic Logic UnitRegisters10CPU speedSpeed measured in hertzHertz = # of instructions executed per secondMegahertz = 1 million of instructions per secondGigahertz = 1 billion of instructions per secondIntel- Celeron- Pentium 3, Pentium 4, Pentium 4 Xeon, Dual CoreAdvanced Micro Devices (AMD)- K6 series processors (which compete with Intel Pentium 3)- Athlon series (which compete with Intel Pentium 4)IBM- PowerPC 740, 750, 750FX, 750GL, 750GXMajor Processor manufacturers11Primary StorageRAM holds running programs and the data they useROM contains critical programs such as those that boot the computerPrimary StorageRAMROMComputer’s memory stored on semiconductor chipsTwo categories: RAM (Random Access Memory) which is volatileSynchronous Dynamic RAM (SDRAM)Double Data Rate SDRAM or DDR SDRAMROM (Read-Only Memory) which is non-volatileCapacity in Megabytes (MB) or Gigabytes (GB)Program Data12Summary QuestionsBook Notes1) Name three devices that could be used for both input and output.2) What is the difference between: (a) a Kilobyte and a Gigabyte? (b) a Megabyte and a byte?3) What is the function of the Instruction Control Unit or ICU found in the processing subsystem?4) Explain the difference between RAM and ROM.5) What is pixel? What is dot pitch6) What is a byte?7) What is a Hertz?13Software Technology14Relationship of software to hardware15Main Types of SoftwareSystems softwarePrograms that manage computer hardware and application softwareThree types of systems software:Operating systems (e.g. Windows, Linux)Language translators (C++ compiler, VB compiler)Utility programs (e.g. Norton Utilities)Systems SoftwareApplication Software16Main Types of SoftwareApplication softwarePrograms that allow users to accomplish specific tasksExamplesWord processing Web browserTax preparationData managementDesktop publishingE-mailGroupwarePresentation graphicsProgramming editorsSpreadsheet17Operating Systems (OS)Software platform on which other programs runProvides a connection between application programs and the computer hardwareMajor tasksStarting the computerManaging filesManaging Programs and Memory (RAM)Ensuring securityProviding a user interfaceExample of OS: Linux, Windows XP, Windows 2000, UNIX.18Managing Memory: Multiprogramming19￭ A technique that “extends” primary memory (RAM) by using secondary storage devices ￭ Needed when there is not enough RAM to hold programsManaging Memory: Virtual Memory20Summary QuestionsBook Notes1) What are the functions (or tasks) of an OS?2) What do application programs allow?3) What is the function of the Instruction Control Unit or ICU found in the processing subsystem?4) What is meant by virtual memory?5) What is meant by multiprogramming?21Network Technology22Computer NetworkAn interconnection of computers and computing equipment using either wires or radio waves over small or large geographic distances“Connect to GHI”ABCDEFGHIJKLMNOOnce connected to the network, the computer (or another device) becomes a network node23Transmission MediaPhysical mediaTransmission media used to physically connect nodes in to the networkTransmits electrical or optical signalsCould be cooper wire or fiber optic cablePhysicalWireless24Transmission Media (Continued)Twisted PairCategory Use Signal Data rate Distance ProblemCategory 1 Telephone Analog/Digital <100Kbps 3-4 miles Security, noiseCategory 2 T1, ISDN Digital <2 Mbps 3-4 miles Security, noiseCategory 3 LANs Digital 10 Mbps 100 m Security, noiseCategory 4 LANs Digital 20 Mbps 100 m Security, noiseCategory 5 LANs Digital 100 Mhz 100 m Security, noiseCategory 6 LANs Digital 250 Mhz 100 m Security, noiseCategory 7 LANs Digital 600 Mhz 100 m