Storage Devices

Angela BaskervilleJessie Huynh

Michael LucadoJames Onley III

What is a storage device?

Any device on which data can be stored.

Common Types of Storage Devices 

FDDHDDSolid State vs. MagneticOptical DrivesCD/DVD/RW Blu-RayRemovable StorageTape DriveSolid StateExternal CD-RWHot Swappable &non hot swappable

Hard Disk Drive (HDD)

•Invented by Reynold Johnson in 1956•Used in the IBM 305 RAMAC accounting computer•Actuator saves data to the platters magnetically •Most HDDs are connected to the motherboard using a 1 meter SATA-device cable

http://www.youtube.com/watch?v=t6wTZhsffEE

Hard Disk Drive (HDD)

Solid State Drive (SSD)

•SSD technology has been around since 1978•Flash based SSD introduced by M-Systems in 1995•Uses non-volatile flash memory to store data•Volatile SSDs that use DRAM are also available

HDD vs. SSD

HDD vs. SSD

•HDD-–Cheaper–Higher capacity (2-3 TB)–Faster write time http://www.youtube.com/watch?v=eOoW8v9UyTA

•SSD-–Faster data access–Less noise–Less power consumption–More reliable

HDD vs. SSD

•HDDs have slower data access times due to the data being fragmented on the hard disk•Defragmenting data increases data access time•Data saved on SSDs does not need to be read sequentially so there is no need for defragmenting http://www.youtube.com/watch?v=iE__2gBxL9Y

Floppy Disks• Term “floppy disk” first used to refer to the 8” medium used

with mini-computers and mainframes• Then was used to refer to the PC floppy diskette which used

a 5.25” platter – also called the minifloppy diskette.• Now refers to the 3 1/2" floppy diskette – aka microfloppy

diskette.  This is the version that is used in computers today if any floppy technology is used at all.

 

Floppy Disks (cont.)

Floppy Drive Size    Tracks/Side    Sectors/Track    Capacity5 1/4" DD                            40                        9               360KB5 1/4" HD                            80                       15              1.2MB3 1/2" DD                            80                        9               720KB3 1/2" HD                            80                       18              1.44MB3 1/2" ED                            80                       36               2.88MB      DD = Double DensityHD = High DensityED = Extended Density

Floppy Disks (cont.)• Floppy disk: magnetic storage

medium that uses a thin, flexible plastic diskette enclosed in a hard plastic casing

• Before the advent of thumb drives, enabled information to be transported easily from one computer to another.

• Too small for today’s information needs, was replaced by CD-ROMs and DVD-ROMs, then by solid state storage.

Floppy Diskette Drives (FDD)

• Floppy diskette drive (FDD) is used to read and write information from floppy disks.

 • Pro: Allow portability of data• Con:  Limited storage capacity.

            • Even though the physical form factor is similar to hard

drives, the technology is incompatible and floppy disks can only store one or two mbps of data 

 • http://www.youtube.com/watch?v=cxhU0wXsKEM

 

Optical Drives

• Enables a computer to read different types of media discs• Some drive can only read discs, but recent drives are both

reader and recorders

How Does an Optical Drive Work?

• Three layers: the plastic disc part on the bottom, a reflective surface in the middle, and the top part of the disc, in which protects the data itself.

   

Continued

• A laser focuses a beam of light on the reflective layer on the optical disc

• The beam focused on pits is scattered, whereas on lands it is reflected back with higher intensity and is stored in photo diode array

• Burning a CD, it involves use of a mold to stamp press the data in pits on the reflective layer in the disc

http://www.youtube.com/watch?v=ESpL4a08kVE&feature=related

CD-Media

• CD-ROM• CD-R was introduced in the mid-1990s• Early CD-R drives requires that the entire disc be burned in

one session, which are called single-session drives• Modern CD-R allow users to go back and burn additional

data until it is full, which are called multisession drives• Once the data is burned onto the CD-R disc, the data

cannot be erased or altered • have two speeds that matter: record speed & read speed

o Ex: 8x24x• Two types of CD-R disc:

o 74-minute disc that holds approximately 650 MBo 80-minute disc that holds approximately 700 MB

CD-Media Continued

• CD-RW drives not only allows users to burn data onto a disc, but to burn over existing datao Three values:

first shows the CD-R write speed second shows the CD-RW rewrite speed third shows the read speed

example: 8x4x32x

DVD-Media

• Develop by a large consortium of electronics and entertainment films during the early 1990s and released in 1995

• Lowest capacity- 4.37 GB of data or two hours of video• Highest capacity-16 GB of data or more than eight hours of

video• Uses smaller pits than CD-Media and packs them more

densely• Comes in single-sided (SS) and double-sided (DS) format• Comes in single-layer (SL) and dual-layer (DL) format

DVD Media Continued

• DVD-ROM• Standard recordable DVD-Media

o DVD-Ro DVD-RWo DVD+Ro DVD+RW

Blu-ray Media

• Developed by Sony• Disc Capacity:

o Single-layer- 25 GBo Dual-layer- 50 GB

• Types:o Standard disc- 12cmo Mini disc- 8cm

• BD-ROM• BD-R• BD-RE

Installing Optical Drives

 http://www.youtube.com/watch?v=EPRxY1-Zz58

Tape Backup Devices• Hard drives will fail - data

must be backed up onto another storage medium

• Older type of removable storage

• Can store large amounts of data

• Can be installed internally or externally

• Use tape magnetic tape medium for storage instead of disks

• Slow - used more for archival storage

Backup Tape Formats

Quarter Inch Cartridge (QIC)Digital Linear Tape (DLT)Eight Millimeter (Exabyte)Digital Data Storage (DDS)Linear Tape-Open (LTO)

External Disk Drives

USB-Attached• Commonly manufactured

in their own chassis• Have detachable

connectivity for USB/FireWire

• If power requirement high enough, may also have power connection - if not, USB connection provides necessary power

• Speed is limited to approx. 50-60 MBps

eSATA-Attached• eSATA = external SATA• Extends the SATA bus to

external devices at full speed

• Connectors are different from internal SATA to avoid confusion

Flash Memory    

Who?Dr. Fujio Masuoka   When?1984  Why it's important?Flash Memory is usually better than traditional memory because it uses less power and is more reliable

Flash Memory cont.

Flash memory refers to a particular type of EEPROM, or Electronically Erasable Programmable Read Only Memory. It is a memory chip that maintains stored information without requiring a power source. It is often used in portable electronics, like MP3 players, and in removable storage devices. 

Flash Memory Applications

• Computer BIOS• Memory Sticks• PCMCIA cards• MP3 Players• Modems• Video Game cards• Cell Phones

  

    Flash memory ≠ RAM

SD Memory

Who? SanDisk, Matsushita, and Toshiba When?1999 Why it's important?SD technology is used by more than 400 brands across dozens of product categories and in more than 8,000 models.

SD Memory

•  MultiMediaCard Upgrade• Card's electrical contacts are recessed beneath the surface

of the card• SDSC, SDHC, SDXC•  All SD card families have the same physical shape•  Basic cards transfer data up to six times the data rate of the

standard CD-ROM speed (7.2 Mb/s vs 1.2 Mb/s).•  Form factor has changed from SD, Mini SD, Micro SD•  SD cards typically have transfer rates in the range of 80–

160 Mb/s•  Other Flash Cards include: Compact Flash, Smart Media,

Memory Stick, xD Picture Cards

ThumbDrive or DiskOnKey

Who? Trek Technology and IBM When?2000 Why it's important?Data stored on flash drives is impervious to scratches and dust

 

Various USB Designs

What's USB used for?

• Personal Data Transport• Secure storage of data, application and software files• System administration• Application carriers• Booting operating systems• Brand and product promotion• Backup• Flash drives also store data densely compared to many

removable media

Disadvantages

• Unsupervised visitors or employees to store and smuggle out confidential data with little chance of detection.

• Vulnerable to  keyboard loggers or packet sniffers.

• Deliberately or unwittingly to transfer malware and autorun worms onto a network.

Hot-Swappable Devices

 A hot swappable device is one which can be attached or detached from a computer or other electronic device without having to reboot the computer.The most common hot swappable devices are universal serial bus (USB) devices. Many hot swappable USB devices have all the necessary software built in to the device, so simply plugging it in to the computer allows the computer to detect the USB device and start working with it. Firewire is another common interface used with hot swappable devices. eSATA also.

Sources

• http://www.opticsetc.com/how-does-an-optical-drive-work.html

• http://www.notebookreview.com/default.asp?newsID=4683• http://www.ncsu.edu/it/essentials/your_computer/

hardware_specs/optical_drive.html• CompTIA A+ Certification by Mike Meyers• http://www.geeknewscentral.com/2010/04/26/tribute-to-

floppy-disk-as-sony-discontinues-production/• http://www.hardwaresecrets.com/article/Anatomy-of-a-

Floppy-Disk-Drive/180/2• http://www.tomshardware.com/reviews/backing-tape-

drives,593.html• http://www.pctechguide.com/

31HardDisk_SolidStateDrives.htm  • http://compreviews.about.com/od/storage/a/SSD.htm

1)  What is the physical component where data are stored in a       HDD?     A.  Read/Write head    B.  Platter    C.  Sector    D.  Cluster

Answer:  B.  PlatterA conventional HDD contains discs called platters, on which data are stored magnetically through read/write heads by way of a magnetic coating.

2)  High-density 3 ½” floppy diskettes have a formatted                 capacity of:    A.  360KB    B.  720KB    C.  1.44MB    D.  2.88MB

Answer:   C.  1.44MB

3) Which of the following best describes the concept of                hot-swappable devices?    A.  Power does not need turned off before the device is                 inserted or removed.    B. The device can be removed with power applied after the         device is properly stopped in the operating system.        C. Care must be taken when swapping the device because          it can be hot to the touch.    D. The device can be swapped while still hot, immediately             after powering down the system.

Answer:   AHot-swappable devices can be removed while the power to the system is still on.  Warm-swappable devices need to be stopped in he operating system before being removed.  The term has nothing to do with the heat level of the device.

4)  What kind of media is most commonly used when large         amounts of data need to be archived on a regular basis?    A.  Tape    B.  Optical Drive    C.  External hard drive    D.  Floppy diskette

Answer:   AAlthough inefficient as an interactive medium, sequential tape-based storage continues to be developed in increasing capacities.  Tape remains the best choice for frequently backing up large amounts of data for redundancy and archival purposes.

5)  What is the maximum cable length of an internal SATA             device?    A.  2 meters    B.  12 inches    C.  18 inches    D.  1 meter

Answer:  DThe maximum cable length of an internal SATA device is 1 meter.

6) To install a floppy drive as the A: drive, what must you do?    A.  Attach the mini connector    B.  Plug it into the end connector of the ribbon cable    C.  Plug it into the middle connector on the ribbon cable    D.  Attach the Molex connector

Answer:  BPlug the floppy drive into the end connector of the ribbon cable.

7)    If the floppy disk you used last week will not work today in        your floppy drive, what should you do first to determine if           the problem is the drive or the disk?    A.  Try another disk in the drive or try the disk in another                 drive.    B.  Open the computer and check the ribbon cable.    C.  Replace the floppy drive.    D.  Check the CMOS settings.

Answer:  ATry another disk in the drive or try the disk in another    drive.

8) Which term describes the capability to burn files to a CD-R        and then come back later and burn additional files?    A.  MultiBurn    B.  Multisession    C.  MultiDrive    D.  Multibuffer

Answer:  BThe term multisession describes the capability to burn files to a CD-R and then come back later and burn additional files.

9)    Which type of flash memory card is currently the most                popular?    A.  CompactFlash    B.  Memory Stick    C.  Secure Digital    D.  SmartMedia

Answer:  C.  Secure Digital

10)  A CD-RW has a speed rating of 12x10x32x.  What do the           three numbers refer to, in order?    A.  Write, rewrite, read    B.  Read, write, rewrite    C.  Rewrite, read, write    D.  Write, read, rewrite

Answer:  A.  Write, rewrite, read