Computers13 Ch6

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Computers13 Ch6

  1. 1. Storage and Multimedia Chapter 6 B.M.H
  2. 2. Index <ul><li>Magnetic Tape Storage </li></ul><ul><li>Optical Disk Storage </li></ul><ul><li>Multimedia </li></ul>
  3. 3. Secondary Storage <ul><li>Magnetic storage </li></ul><ul><ul><li>Disk storage </li></ul></ul><ul><ul><ul><li>Floppy disk </li></ul></ul></ul><ul><ul><ul><li>Hard disk </li></ul></ul></ul><ul><ul><li>Tape storage </li></ul></ul><ul><li>Optical storage </li></ul><ul><ul><li>CD </li></ul></ul><ul><ul><li>DVD </li></ul></ul>
  4. 4. Magnetic disk storage
  5. 5. Magnetic Tape Storage <ul><li>Plastic tape with a magnetic coating </li></ul><ul><ul><li>Looks like the tape used in music cassettes </li></ul></ul><ul><li>Magnetic media </li></ul><ul><ul><li>Data is stored as extremely small magnetic spots </li></ul></ul>
  6. 6. Magnetic Tape Storage <ul><li>Form </li></ul><ul><ul><li>½-inch-wide tape wound on a reel </li></ul></ul><ul><ul><li>¼-inch-wide in data cartridges and cassettes </li></ul></ul><ul><ul><li>Tapes like ordinary music cassettes </li></ul></ul>
  7. 8. Magnetic Tape Storage <ul><li>Capacity </li></ul><ul><ul><li>Expressed in terms of density </li></ul></ul><ul><ul><ul><li>: which is the number of </li></ul></ul></ul><ul><ul><ul><li>characters per inch (cpi) or </li></ul></ul></ul><ul><ul><ul><li>bytes per inch (bpi) </li></ul></ul></ul><ul><ul><ul><li>that can be stored on the tape </li></ul></ul></ul>
  8. 9. Magnetic Tape Storage <ul><li>The primary role of tape, today </li></ul><ul><ul><li>An inexpensive backup medium </li></ul></ul><ul><ul><ul><li>Because disks are the superior storage medium </li></ul></ul></ul><ul><ul><ul><ul><li>Quite reliable within as sealed module </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Can be accessed directly, in contrast to sequential data on tape </li></ul></ul></ul></ul>
  9. 10. Backup Systems <ul><li>The causes of loss of data on a hard disk </li></ul><ul><ul><li>Physical damage </li></ul></ul><ul><ul><ul><li>from fire and natural disasters </li></ul></ul></ul><ul><ul><li>Electromechanical failures </li></ul></ul><ul><ul><li>Errors introduced by users </li></ul></ul><ul><ul><li>Errors introduced by software </li></ul></ul><ul><ul><li> Backup is vital </li></ul></ul>
  10. 11. Backup System <ul><li>A way of storing data in more than one place to protect it from damage and errors </li></ul><ul><li>The primary storage for backup </li></ul><ul><ul><li>Magnetic tape </li></ul></ul>
  11. 12. Backup System <ul><li>Tape backup system </li></ul><ul><ul><li>Copying all data from hard disk to a single tape in minutes </li></ul></ul><ul><ul><li>Can be scheduled to take place when you do not use the computer </li></ul></ul><ul><ul><li>Tape cartridges with more than 10GB </li></ul></ul><ul><ul><ul><li>available at reasonable cost </li></ul></ul></ul><ul><li>CD-R, and CD RW media for backup </li></ul><ul><ul><li>Limited to storing less than 1GB of data </li></ul></ul>
  12. 14. Optical disk storage <ul><li>Stores data as microscopic light and dark spots on the disk surface </li></ul><ul><ul><li>The dark spots </li></ul></ul><ul><ul><ul><li>Called pits </li></ul></ul></ul><ul><ul><ul><li>Represent as the 1s </li></ul></ul></ul><ul><ul><li>The lighter, non-pitted surface areas </li></ul></ul><ul><ul><ul><li>Called lands </li></ul></ul></ul><ul><ul><ul><li>Represent as the 0s </li></ul></ul></ul>
  13. 15. Optical disk storage <ul><li>Technology </li></ul><ul><ul><li>: A laser hits a layer of metallic material spread over the surface of a disk </li></ul></ul><ul><ul><li>To write data </li></ul></ul><ul><ul><ul><li>Heat from the laser produces tiny spots, or pits, on the disk surface </li></ul></ul></ul><ul><ul><li>To read data </li></ul></ul><ul><ul><ul><li>The laser scans the disk, and a lens picks up light reflections from the spots </li></ul></ul></ul>
  14. 17. Optical disk storage <ul><li>Advantage </li></ul><ul><ul><li>Inexpensive and compact storage with greater capacity </li></ul></ul><ul><ul><li>Less affected to environmental damage than magnetic media </li></ul></ul>
  15. 18. Optical storage technology <ul><li>Category </li></ul><ul><ul><li>: According to its read/write capability </li></ul></ul><ul><ul><li>Read-only media </li></ul></ul><ul><ul><li>WORM media </li></ul></ul><ul><ul><li>MO media </li></ul></ul>
  16. 19. Optical storage technology <ul><li>Read-only media </li></ul><ul><ul><li>Recorded by the manufacturer </li></ul></ul><ul><ul><li>Can be read from by the user </li></ul></ul><ul><ul><ul><li>but not written to by the user </li></ul></ul></ul><ul><ul><li>Used to supply software </li></ul></ul><ul><ul><ul><li>not for user’s files </li></ul></ul></ul>
  17. 20. Optical storage technology <ul><li>WORM media </li></ul><ul><ul><li>: Write-Once, Read-Many </li></ul></ul><ul><ul><li>May be written to once </li></ul></ul><ul><ul><li>Once filled, it becomes a read-only medium </li></ul></ul><ul><ul><li>Nonerasaible </li></ul></ul><ul><ul><li>Used for secure storage of original versions of valuable documents or data </li></ul></ul>
  18. 21. Optical storage technology <ul><li>MO media </li></ul><ul><ul><li>: Magneto-Optical </li></ul></ul><ul><ul><li>Hybrid type of disk : Combines the best features of magnetic and optical disk technologies </li></ul></ul><ul><ul><ul><li>Has the high-volume capacity of an optical disk </li></ul></ul></ul><ul><ul><ul><li>Can be written over like a magnetic disk </li></ul></ul></ul>
  19. 22. Optical disk storage <ul><li>Types </li></ul><ul><ul><li>CD: C ompact D isks </li></ul></ul><ul><ul><li>DVD : D igital V ersatile D isks </li></ul></ul>
  20. 23. Compact disks <ul><li>Technology </li></ul><ul><ul><li>An optical technology that uses the same media used for audio CDs </li></ul></ul><ul><li>Computer CD drives </li></ul><ul><ul><li>Can play audio CDs, with the proper software </li></ul></ul>
  21. 24. Compact disks <ul><li>Types </li></ul><ul><ul><li>; according to the ability to read and write </li></ul></ul><ul><ul><li>CD- ROM </li></ul></ul><ul><ul><li>CD- R </li></ul></ul><ul><ul><li>CD- RW </li></ul></ul>
  22. 25. Compact disks <ul><li>CD- ROM </li></ul><ul><ul><li>: Compact Disk Read-Only Memory </li></ul></ul><ul><ul><li>Storage : up to 700 megabytes per disk </li></ul></ul><ul><ul><li>Format : identical to that of audio CD </li></ul></ul><ul><ul><li>The primary medium for SW distribution </li></ul></ul><ul><li>CD-ROM drive </li></ul><ul><ul><li>Capable only of reading data from CDs </li></ul></ul>
  23. 26. Compact disks <ul><li>CD- R </li></ul><ul><ul><li>: Compact Disk-Recordable </li></ul></ul><ul><ul><li>Permits writing just once on optical disk </li></ul></ul><ul><ul><li>Requires a CD-R drive, special CD-R disks and the CD-R software </li></ul></ul><ul><ul><li>Once written on, it can be read also by CD-ROM drive, not only CD-R </li></ul></ul>
  24. 27. Compact disks <ul><li>CD- RW </li></ul><ul><ul><li>: Compact Disk-ReWritable </li></ul></ul><ul><ul><li>Allow to erase and record over data multiple times </li></ul></ul><ul><ul><li>Requires a CD-RW drive, special CD-RW disks and the CD-RW software </li></ul></ul><ul><ul><li>Most of today’s optical drives now read CD-RW disks </li></ul></ul>
  25. 28. Digital Versatile Disk <ul><li>Originally D igital Video D isk </li></ul><ul><li>Technology </li></ul><ul><ul><li>A variation of CD technology that was designed to provide enough storage capacity for a full-length movie </li></ul></ul><ul><ul><li>Uses a laser with a shorter wavelength </li></ul></ul><ul><ul><ul><li>permitting it to read more densely packed spots </li></ul></ul></ul><ul><ul><ul><li>thus increasing the disk capacity </li></ul></ul></ul>
  26. 29. DVD <ul><li>Types </li></ul><ul><ul><li>DVD- ROM </li></ul></ul><ul><ul><li>DVD- RAM </li></ul></ul><ul><ul><li>DVD+ RW </li></ul></ul>
  27. 30. DVD-ROM <ul><li>Capacity </li></ul><ul><ul><li>Single-sided : up to 4.7-gigabyte </li></ul></ul><ul><ul><ul><li>Double-layered DVD : about 8.5-GB </li></ul></ul></ul><ul><ul><li>Double-sided : to 17-GB </li></ul></ul><ul><li> Diskette (*450) << CD-ROM (*7) < DVD-ROM </li></ul>
  28. 31. DVD-ROM <ul><li>Used for holding movies </li></ul><ul><ul><li>Exquisite sound, full-length movies </li></ul></ul><ul><li>Suited for distributing large multimedia applications </li></ul><ul><ul><li>Games, encyclopedias, maps, and telephone number databases </li></ul></ul><ul><li>Require a DVD drive </li></ul><ul><ul><li>Also can read data from CD-ROM, CD-R and CD-RW </li></ul></ul>
  29. 32. DVD-RAM <ul><li>Writable version of DVD </li></ul><ul><li>Stores 5.2-GB on a double-sided disk </li></ul><ul><li>Readable only by DVD-RAM drives </li></ul>
  30. 33. DVD+RW <ul><li>Technology very similar to CD-RWs </li></ul><ul><li>DVD-RAM and DVD+RW technologies are not compatible </li></ul><ul><ul><li>Disks created by a DVD-RAM drive cannot be used in a DVD+RW drive, and vice versa </li></ul></ul>
  31. 34. Multimedia
  32. 35. Multimedia <ul><li>Requires sound and graphics capability </li></ul><ul><li>Equipment </li></ul><ul><ul><li>CD-ROM or DVD-ROM drive </li></ul></ul><ul><ul><li>Sound card or sound chip </li></ul></ul><ul><ul><ul><li>Speakers </li></ul></ul></ul><ul><ul><ul><li>Headphones </li></ul></ul></ul><ul><ul><ul><li>Microphone </li></ul></ul></ul><ul><ul><li>Graphics card </li></ul></ul><ul><ul><li>Speedy processor chip </li></ul></ul>
  33. 36. Multimedia Equipment <ul><li>CD-ROM or DVD-ROM drive </li></ul><ul><ul><li>To access audio and software CD/DVD-ROMs </li></ul></ul><ul><ul><li>Multimedia elements had better be stored on a CD-ROM /DVD-ROM than on a hard disk </li></ul></ul><ul><ul><ul><li>For the amounts of the multimedia data are huge </li></ul></ul></ul><ul><ul><ul><li>Insert only when user want to access them </li></ul></ul></ul><ul><ul><li>The higher the drive speed, </li></ul></ul><ul><ul><ul><li>the faster the transfer of data and </li></ul></ul></ul><ul><ul><ul><li>the smoother the video showing on the screen </li></ul></ul></ul>
  34. 37. Multimedia Equipment <ul><li>Sound card </li></ul><ul><ul><li>Gives a computer the capability to record and play sound files </li></ul></ul><ul><ul><li>Contains connectors to attach speakers, headphones and a microphone </li></ul></ul><ul><ul><li>High-performance sound card </li></ul></ul><ul><ul><ul><li>include circuitry for special audio effects such as 3-D sound </li></ul></ul></ul>
  35. 38. Multimedia Equipment <ul><li>The quality of speakers and headphones </li></ul><ul><ul><li>Affect the quality of the sound that user hears </li></ul></ul>
  36. 39. Multimedia Equipment <ul><li>Speaker </li></ul><ul><ul><li>Inexpensive one </li></ul></ul><ul><ul><ul><li>Provide basic radio-quality sound </li></ul></ul></ul><ul><ul><li>Top-quality </li></ul></ul><ul><ul><ul><li>Boosts the bass sound and screens out background noise </li></ul></ul></ul>
  37. 40. Multimedia Equipment <ul><li>Headphone </li></ul><ul><ul><li>Inexpensive one </li></ul></ul><ul><ul><ul><li>Can be used from a portable CD player </li></ul></ul></ul><ul><ul><li>Better-quality </li></ul></ul><ul><ul><ul><li>Produce clearer sound </li></ul></ul></ul>
  38. 41. Multimedia Equipment <ul><li>Microphone </li></ul><ul><ul><li>Basic </li></ul></ul><ul><ul><ul><li>Suitable for voice recording and dictation </li></ul></ul></ul><ul><ul><li>Professional </li></ul></ul><ul><ul><ul><li>For recording instrumental music and vocals </li></ul></ul></ul>
  39. 42. Multimedia Equipment <ul><li>Graphics card </li></ul><ul><ul><li>Takes signals from the processor and uses them to “paint” an image on the screen </li></ul></ul><ul><ul><li>Provides a connection for the monitor’s data cable </li></ul></ul><ul><ul><li>“ accelerated” graphics cards </li></ul></ul><ul><ul><ul><li>equipped with circuitry that optimizes to display videos </li></ul></ul></ul>
  40. 43. Multimedia Equipment <ul><li>Processor </li></ul><ul><ul><li>should quickly handle the huge amount of digital data for multimedia </li></ul></ul><ul><ul><li>The faster the processor, the more data it can process each second </li></ul></ul><ul><ul><li>; the better multimedia quality </li></ul></ul><ul><ul><ul><li>smooth video sequences </li></ul></ul></ul><ul><ul><ul><li>a sound track perfectly coordinated with the action </li></ul></ul></ul><ul><li>Processor chips </li></ul><ul><ul><li>with Intel’s MMX or AMD’s 3DNow! </li></ul></ul><ul><ul><ul><li>Enhance a computer’s multimedia performance </li></ul></ul></ul>

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