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Chapter 7 Storage. Chapter 7 Contents. Storage. Miniature mobile storage media. Magnetic Disks. Microfilm and Mocrofiche. Optical Disks. Enterprise storage. Tape. Putting it all together. PC Cards and Expresscard modules. Storage. What is __________ ?.
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Chapter 7 Contents Storage Miniature mobile storage media Magnetic Disks Microfilm and Mocrofiche Optical Disks Enterprise storage Tape Putting it all together PC Cards and Expresscard modules
Storage What is__________? • Holds data, instructions, and information for future use • _______________is physical material used for storage • Also called secondary storage p. 354 - 355 Fig. 7-1
Storage Kilobyte (KB) 1 thousand Megabyte (MB) 1 million Gigabyte (GB) 1 billion Terabyte (TB) 1 trillion Petabyte (PB) 1 quadrillion Exabyte (EB) 1 quintillion Zettabyte (ZB) 1 sextillion Yottabyte (YB) 1 septillion What is ______________? • Number of bytes (characters) a storage medium can hold p. 356
Storage Memory(most RAM)(chips on motherboard) Screen Display Storage Medium(hard disks, CDs, DVDs,USB flash drives, etc.) How does volatility compare? • Storage medium is ____________—contents retained when power is off • Memory is ________—holds data and instructions temporarily ON OFF Display appears Display disappears Volatile Data andinstructions available to user Data and instructions erased Contents available to user Contents retained Nonvolatile p. 355 - 356
Storage Functions as source of input Creates output What is a________________? Hardware that records and retrieves items to and from storage media Reading Process of transferring items from storage media to memory Writing Process of transferring items from memory to storage media p. 356
Storage What is_____________? • The speed of storage devices and memory measuring • Time it takes storage device to locate item on storage medium • Time required to deliver item from memory to processor p. 357 Fig. 7-4
Magnetic Disks : use magnetic particles ________is narrow recording bandthat forms fullcircle on disk __________stores up to512 bytesof data What are______ and________? p. 357 Fig. 7-5
Magnetic Disks : use magnetic particles For reading and writing purposes, sectors are grouped into _______________. A_______________________is the smallest unit of disk space that stores data and information, and consists of two to eight sectors Even if a file consists of only a few bytes, it uses an entire cluster. Each cluster holds data from only one file, but one file can span many clusters. p. 357 Fig. 7-5
Magnetic Disks Perpendicular recording Longitudinal recording What is a______________? • High-capacity storage • Consists of several inflexible, circular platters that store items electronically • Components enclosed in airtight, sealed case for protection p. 358 Fig. 7-6
Magnetic Disks Sample Hard Disk Characteristics Advertised capacity 500 GB Platters 4 Read/write heads 8 Cylinders 16,383 Bytes per second 512 Sectors per track 63 Sectors per drive 973,773,168 Revolutions per minute 7,200 Transfer rate 300 MBps Access time 8.5 ms What are characteristics of a hard disk? actualdiskcapacity p. 359 Fig. 7-7
Magnetic Disks How does a hard disk work? p. 360 Fig. 7-8
Magnetic Disks Top view of platter What is a_________? track • Vertical section of track through all platters sector • Single movement of read/write head arms accesses all plattersin ________ read/writehead side view of platter platter sides p. 360 Fig. 7-9 cylinder
Magnetic Disks What is a___________? • Occurs when read/write head touches platter surface • Usually resultiing in a loss of data or sometimes loss of the entire drive • Spinning creates cushion of air that floats read/write head above platter p. 360-361 Fig. 7-10
Magnetic Disks first requestfor data—to disk cache second requestfor data—to hard disk What is a_____________? • Portion of memory that processor uses to store frequently accessed items p. 361 Fig. 7-11
Magnetic Disks What is _________? • Redundant Array of Independent Disks • A group of two or more integrated hard disks • Connects multiple smaller disks into a single unit that acts as a single large hard disk p. 362
Magnetic Disks What is a ______________________? • Provide greater storage capacities than flash memory • Smaller than notebook computer hard disks • A __________________, as another type of miniature hard disk, is a self-contained unit p. 362 Fig. 7-13
Magnetic Disks What are_______hard disksand______________hard disks? • Used to back up or transfer files __________hard disk—hard diskthat you insert and removefrom hard disk drive __________ hard disk—freestandinghard disk that connects to system unit p. 363 Fig. 7-14
Magnetic Disks EIDE (EnhancedIntegratedDrive Electronics) controller supports four hard disks, provides connections for CD and DVD drives SCSIcontroller supports up to fifteendevices including hard disks, CDand DVD drives, tape drives, printers, scanners, network cards SATA (Serial Advanced Technology Attachment) controller uses serial signals to transfer data, instructions, and information SAScontroller supports many connecteddevices at once, including hard disks,CD and DVD drives, printers,scanners, digital cameras, and more What is a_________________? • Chip and circuits that control transfer of items from disk p. 363 - 364
Magnetic Disks What is ________________? • Service on Web that provides storage for minimal monthly fee • Files can be accessed from any computer with Web access • Large files can be downloaded instantaneously • Others can be authorized to access your data p. 364 - 365 Fig. 7-15
Magnetic Disks What is a____________? • Portable, inexpensive storage medium (also called diskette) Thin, circular, flexible film enclosedin 3.5” wide plastic shell p. 365 Fig. 7-16
Optical Discs What are____________? • Flat, round, portable metal discs made of metal, plastic, and lacquer • Can be read only or read/write • Most PCs include an optical disc drive p. 366 Fig. 7-17
Optical Discs disc label lens lens pit land Step 3.Reflected light is deflected to alight-sensing diode, which send a digital signals of 1 to computer. Absenceof reflected light is read as a digital signal of 0. 0 1 prism prism light-sensingdiode light-sensingdiode laserdiode laserdiode How does a laser read data on an optical disc? Step 2.If light strikesa pit, it scatters. If light strikes a land, it is reflected back toward diode. Step 1.Laser diode shines a light beam towarddisc. p. 367 Fig. 7-18
Optical Discs How is data stored on an optical disc? • Typically stored in singletrack • Track divided into evenly sizedsectorsthat store items p. 367 Fig. 7-19
Optical Discs What is a____________? • Compactdiscread-onlymemory • Cannot erase or modify contents • Typically holds 650 MB to 1 GB • Commonly used to distribute multimedia and complex software p. 369 Fig. 7-22
Optical Discs What is the data transfer rate of a CD-ROM drive? Ranges from 48X to 75X or faster 75X 75 150 KBps = 11,250 KBps or 12.25 MBps 75X is 150 KBps (KB per second) 48X: 48 150 KBps = 7,200 KBps or 7.2 MBps p. 369
Optical Discs What are________ and ___________? Must haveCD recorderor CD-R drive (compact disc-recordable) —cdisc you can write on once Cannot erasedisc’s contents _________ (compact disc-rewritable) —ceerasable disc you can write onmultiple times Must haveCD-RW softwareandCD-RW drive p. 370
Optical Discs What is an_____________? Stores photos from an online photo center in the jpg file format. p. 370 - 371 Fig. 7-23
Optical Discs What is a___________(digital versatile disc-ROM or digital video disc-ROM)? • Stores databases, music, complex software, and movies • Blu-ray discs have storage capacity of up to 100 GB • HD-DVD discs have storage capacity of up to 60 GB • HD-VMDs have storage capacity of up to 40 GB or more • UMD can store up to 1.8 GB p. 372 Fig. 7-24
Tape What is________? • Magnetically coated plastic ribboncapable of storing large amountsof data at low cost • Primarily used for backup p. 374 Fig. 7-27
Tape How is data stored on a tape? • Sequential access • Reads and writes data consecutively, like music tape • Unlike direct access — used on hard disks, CDs, and DVDs — which can locate particular item immediately p. 374
PC Cards and ExpressCard Modules Removable devices. • ____________________: a thin credit card sized removable flash memory deice. • _____________________________________: a removable device, smaller than ______________. • They can be used for adding memory, storage, communications, multimedia, and security capabilites. p. 374 Figs. 7-28
Miniature Mobile Storage Media What isminiature mobile storage media? • Storage for small mobile devices p. 375 Fig. 7-29
Miniature Mobile Storage Media What are common types of flash memory cards? p. 376 Fig. 7-30
Miniature Mobile Storage Media What is a_______________? • Plugs in a USB port on a computer or mobile device • Storage capacities up to 64 GB • May eventually make the floppy disk nearly obsolete p. 377 Fig. 7-32
Miniature Mobile Storage Media What is a______________? • Stores data on microprocessor embedded in small card • Input, process, output, and storage capabilities p. 378 Fig. 7-33
Microfilm and Microfiche _____________ — 100- to215-foot roll of film _________— small sheet of film, usually 4” 6” What are______________and__________? Store microscopic images of documents on roll or sheet of film Images recorded using computer output microfilm recorder p. 379 Fig. 7-34
Microfilm and Microfiche How do life expectancies of various media compare? • Microfilm and microfiche have longest life of any storage media p. 379 Fig. 7-35
Putting It All Together What are recommended storage devices for home users? • 320 GB hard disk • Online storage • CD or DVD drive • Card reader/writer • USB flash drive p. 380 Fig. 7-37
Putting It All Together What are recommended storage devices for small office/home office (SOHO) users? • 1 TB hard disk • Online storage • CD or DVD drive • External hard drive for backup • USB flash drive p. 380 Fig. 7-37
Putting It All Together What are recommended storage devices for mobile users? • 250 GB hard disk • Online storage • CD or DVD drive • Card reader/writer • Portable hard disk for backup • USB flash drive p. 380 Fig. 7-37
Putting It All Together What are recommended storage devices for power users? • 2.5 TB hard disk • Online storage • CD or DVD drive • Portable hard disk for backup • USB flash drive p. 380 Fig. 7-37
Putting It All Together What are recommended storage devices for large business users? • Desktop computer • 1 TB hard disk • CD or DVD drive • Smart card reader • Tape drive • USB flash drive • Server or Mainframe • Network storage server • 40 TB hard disk system • CD or DVD server • Microfilm or microfiche p. 380 Fig. 7-37
Summary of Storage Internal hard disks HD DVD discs External and removable hard disks Recordable and Rewritable DVDs Floppy disks Tape CD-ROMs PC Cards and ExpressCard modules Recordable and Rewritable CDs Flash memory cards and USB flash drives DVD-ROMs Smart cards, microfilm, and microfiche Blu-ray Discs (BDs) Chapter 7 Complete