1. Computer Hardware Computers and components

4. Basic Computer System MAIN MEMORY ALUCNTL..... BUS CONTROLLER Processor I/O moduleInterconnections BUS ATTACHED DEVICE

5. Computer Components

6. CPU Cycle Start FETCHEXECUTE Halt Increment Program Counter FETCHEXECUTE

7. Execution Cycle

8. Instruction Sets Complex (CISC) or Reduced (RISC) ALUCNTL..... ROM INSTRUCTIONS

9. Measuring Processing Power zClock Speed zInstruction Speed zWord Length and Bus Width zSpeed of Arithmetic zInstruction Set zPipelining

10. Primary Storage zVolatile yDRAM ySRAM yCache zNonvolatile yROM

11. zKilobytesKB1,000 B Text document zMegabytesMB1,000,KB Images zGigabytesGB1,000 MB Hard disk drives zTerabytesTBTrillions Data warehouse files Measuring Storage (bytes)

12. Attached I/O Devices zSecondary Storage yDASD yTape yRemovable Electronic Storage yOptical (etc.) devices z Communication Devices yModems and Codecs yLAN’s, Backbones and WAN’s yRouters and other node devices

13. Secondary Storage Devices Fixed Media hard disks RAID Removable Media diskette laser-servo diskette cartridge disks tape CD-ROM flash memory

14. Attached Devices zHardware: device itself such as a disk or video display device. zElectronics: controller that communicates with the device zSoftware: device driver that is loaded into the computer operating system

15. Local and Peripheral Bus

17. Data Transfer: MAIN MEMORY BUFFER CPU TAAD CONTROLLER DASD CPU CHANNEL

18. I/O Controller (DASD) PROCESSOR REGISTER BUFFER

19. Direct Access Storage Device (DASD)

20. DASD Structure Read-Write Heads

21. Cylinder/Track/Block Block (Sector)Track Cylinder

22. Disk Organization

23. Data Storage zFAT (File Access Tables), Directories and Catalogs zUpdate and Delete zFragmentation and reorganization zBlocks, Headers and Interblock Gaps

24. Hardware II

25. General Purpose Computing zSoftware primacy Applications are controlled by changing the instructions run by the computer, rather than by changing the hardware zASIC’s and Firmware Any program that can be written in software can also be burned onto a chip as a family of circuits

26. Computer Classifications Size ymainframe ymidrange ymicrocomputer Function ylegacy mainframe yserver yrouter yclient

27. Mainframe (Legacy) zTuned for transaction processing zHas channels to support very large numbers of attached devices zRuns a mainframe operating system zTend to support legacy software

28. Client/Server Architectures SERVER PROCESSING CLIENT PROCESSING CENTRALIZEDSTAND-ALONE FAT SERVER FAT CLIENT

29. Client/Server Architecture An architecture in which the client (personal computer or workstation) is the requesting machine and the server is the supplying machine, both of which are connected via a network.

30. Client/Server Architecture zClient zMay do some or all of the processing zRequests services from the network z Server z Contains data and may contain programs z Server downloads information (applications or data) to the client for operation

31. Client zUse relatively inexpensive computer chips (Intel or Motorola) zHave a single processor zOptimized for user convenience zSingle user zLimited numbers of attached devices

32. Server zUse inexpensive CPU chips zDesigned with redundant components zHave large internal memory capacity zMay not need very fast CPU capability

33. Three Tier Client/Server

34. Any time Any place Any way

35. Router zUsed to segment networks and prepare message packets for transmission zSpecial purpose operating system to read and forward message packets zMay support firewall functions zSupport special purpose CPU chips and optimized network sysems

36. Routers Input Buffer Proces- sor Output Buffer From AFrom B To CTo D Table of Addresses Input Buffer Output Buffer

37. zCentral Architecture zClient/Server zWeb Access