Your SlideShare is downloading. ×
Ch5 storagedevices(updated)
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Ch5 storagedevices(updated)

3,301

Published on

0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
3,301
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
329
Comments
0
Likes
2
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide
  • لا مغناطيس أو ليزر
  • الوقت للعثور على البيانات المطلوبة
  • معدل نقل البيانات
  • تمت معالجتها بواسطة نظام التشغيل ( OS)  أداة
  • تحسين الأداء
  • Transcript

    • 1. Chapter 5 Types of Storage Devices
    • 2. Describing Storage Devices
      • Storage devices hold data permanently, even when the computer is turned off .
      • Two processes
        • Writing data
        • Reading data
      6A-
    • 3. Describing Storage Devices
      • Storage terms
          • The physical material that actually holds data is called a storage medium.
              • A floppy disk is a storage medium.
          • The hardware that writes data to or reads data from a storage medium is called a storage device .
              • A floppy disk drive is a storage device.
      • Types of Storage Devices :
          • Magnetic devices use a magnet
          • Optical devices use lasers
          • Solid-state devices have physical switches
      6A-
    • 4.
      • Magnetic Storage Devices
      • The primary types of magnetic storage are:
            • Hard disks.
            • floppy disks(Diskettes).
            • High-capacity floppy disks.
            • magnetic tape.
      • All magnetic drives work the same
      6A- Floppy Disk Hard Disk Tape
    • 5. Magnetic Storage Devices
      • Data storage and retrieval
        • A magnetic disk's medium contains iron particles,
        • A disk drive uses read/write heads containing
        • electromagnets to create magnetic charges on the
        • medium.
      6A-
    • 6. Magnetic Storage Devices
      • Data organization
        • Disks must be formatted before use
      • Determines how data will be stored:
        • Format draws tracks on the disk
        • Tracks is divided into sectors
      • Purpose of formatting a magnetic disk:
        • Before the computer can use a magnetic disk to store data, the disk’s surface must be magnetically formatted, so that the computer can go directly to a specific point on it without searching through data .
      6A-
    • 7. Tracks and Sectors 6A-
    • 8. Magnetic Storage Devices
      • Finding data on disk
        • Each track and sector is labeled
        • Listing of where files are stored
          • File Allocation Table (FAT)
          • – a log that records each File's location and each sector's status
          • FAT32
          • NTFS
        • The OS(Operating system) organizes sectors into groups, called clusters
      6A-
    • 9. Magnetic Storage Devices
      • Diskettes
        • Also known as floppy disks
        • Spin at 300 RPM
        • Takes .2 second to find data
        • 3 ½ floppy disk holds 1.44 MB
      6A-
    • 10. Magnetic Storage Devices
      • Hard disks
        • Primary storage device in a computer
        • 2 or more aluminum platters
        • Each platter has 2 sides
        • Spin between 5,400 to 15,000 RPM
        • Data found in 9.5 ms or less
        • Drive capacity greater than 40 GB
      6A-
    • 11. Illustrated Hard Disk 6A-
          • Contain multiple disks called platters
    • 12. Magnetic Storage Devices
      • Removable high capacity disks
        • Speed of hard disk
        • Portability of floppy disk
        • There are 2 types :
            • High capacity floppy disk
              • Stores up to 750 MB of data
            • Hot swappable hard disks
              • Provide GB of data
              • Connect via USB
      6A-
    • 13. Magnetic Storage Devices 6A-
        • Hot swappable hard disks
      • Hot swappable hard disk : can be removed and replaced while the computer is still running.
    • 14. Magnetic Storage Devices
      • Tape drives
        • Best used for
          • Infrequently accessed data
          • Back-up solutions
        • Slow sequential access
        • Capacity exceeds 200 GB
      6A-
    • 15. Optical Storage Devices
      • List seven types of optical storage devices commonly used in PCs.
      • Compact Disc Read-Only Memory (CD-ROM).
      • CD-Recordable (CD-R).
      • CD-ReWritable (CD-RW).
      • Digital Video Disc Read-Only Memory (DVD-ROM).
      • DVD-Recordable (DVD-R).
      • DVD-ReWritable (DVD-RW).
      • PhotoCD.
      6A-
    • 16. Optical Storage Devices
      • CD-ROM
        • Most software ships on a CD
        • Read using a laser
        • Written from the inside out
        • Standard CD holds 650 MB
      6A-
    • 17. Recordable Optical Technologies
      • CD Recordable (CD-R)
        • Create a data or audio CD
        • Data cannot be changed
        • Can continue adding until full
      6A-
    • 18. Recordable Optical Technologies
      • CD Rewritable (CD-RW)
        • Create a reusable CD
        • Can reuse about 100 times
      6A-
    • 19. Recordable Optical Technologies
      • Photo CD
        • Provides for photo storage
        • Photos added to CD until full
        • Original pictures cannot be changed
      6A-
    • 20. Optical Storage Devices
      • DVD-ROM
        • Digital Video Disk
        • Use both sides of the disk
        • Capacities can reach 18 GB
        • DVD players can read CDs
      6A-
    • 21. Recordable Optical Technologies
      • DVD Recordable (DVD-R)
        • Allows home users to create DVDs
        • Data cannot be changed
      • DVD-RAM
        • Allow reusing of DVD media
      6A-
    • 22. Solid State Devices
      • Data is stored physically
          • Store data on memory circuits.
      • No magnets or laser
      • Very fast
      • The primary types of Solid State Devices are:
          • Flash memory
          • Smart cards
          • Solid-state disks
      6A-
    • 23. Solid State Devices
      • Flash memory
        • Found in cameras and USB drives
        • Combination of RAM and ROM
        • Long term updateable storage
      6A-
    • 24. Solid State Devices
      • Solid-state disks
        • Large amount of SDRAM
        • Extremely fast.
        • Require battery backups
        • Most have hard disks copying data
      6A-
    • 25. Solid State Devices
      • Solid-state disks
      6A-
    • 26. Solid State Devices
      • Smart cards
        • Credit cards with a chip
        • Chip stores data
        • A smart card contain memory and microprocessor components.
        • The card is made of plastic.
        • Hotels use for electronic keys
      6A-
    • 27. Questions
      • List four types of magnetic storage devices commonly used in PCs.
      • List seven types of optical storage devices commonly used in PCs.
      • Name three types of solid-state storage devices.
      • What is the purpose of formatting a magnetic disk?
      • What is the storage capacity of a standard floppy disk?
      6A-
    • 28. Measuring and Improving Drive Performance
    • 29. Drive Performance
      • Average access time
        • Also known as seek time
        • Time to find desired data
        • Measured in milliseconds(ms)
        • Hard drive between 6 and 12 ms
        • CD between 80 and 800 ms
      6B-
    • 30. Drive Performance
      • Data transfer rate
        • the amount of data that one device can send to another in a given amount of time.
        • Measured in
          • Bps( mega bytes per second )
        • Hard drive ranges from 15 to 160 MBps
        • Floppy disks transfer at 45 KBps
      6B-
    • 31. Data Transfer Rate 6B-
    • 32. Optimizing Performance
      • 1. Disk optimization
        • Handled by operating system(OS) tool
        • Routine disk maintenance
        • Optimization should be run monthly
      6B-
    • 33. Optimizing Performance
      • 2. Clean up unnecessary files
        • Delete temp files
        • Uninstall unused programs
        • Delete obsolete data files
        • Files should be cleaned weekly
      6B-
    • 34. Optimizing Performance
      • 3. Scan a disk for errors
        • Bad spots on the media
        • Find and fix the error
          • Move data to a good spot
          • Mark the spot as bad
        • Disks should be scanned monthly
      6B-
    • 35. Optimizing Performance
      • 4. Defragment a disk
        • Files fragment when resaved
        • Fragmented files load slower
        • Defragment puts the fragments together
        • Disks should be defragged monthly
      6B-
    • 36. Defragment 6B-
    • 37. Optimizing Performance
      • 5.File compression
        • Shrinks the size of a file
        • Takes up less space on disk
        • Reduce a disks performance
        • Will increase disk capacity
        • PKZip, WinZip and WinRAR
      6B-
    • 38. File Compression 6B- 763 KB on disk Compressed 157 KB
    • 39. Chapter 6 End of Chapter

    ×