hardware and software chapter 4. q1: what does a manager need to know about computer hardware?...
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Hardware and Software
Chapter 4
Q1: What does a manager need to know about computer hardware?
Q2: What’s the difference between a client and a server?
Q3: What does a manager need to know about software?
Q4: What buying decisions do you make?
Q5: What are viruses, Trojan horses, and worms?
4-2
Study Questions
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• Dee hires consultant– Specializes in setting up systems like blogs
• Consultant needs answers:– Will blog be run inside or outside Emerson?– Will server be Windows or Linux?– Which blog software will be used?– How will the blog be coded? Dreamweaver? Build HTML
editor?– What browsers need to be supported?– Do you care if blog does not render perfectly with all
browsers?
This Could Happen to You
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• Dee needs information system to support her blog– Actors, Instructions and Bridge
• Needs to consider five components of information systems
1. People: sales force and herself2. Hardware: server3. Procedures: for posting, accessing blog, leaving
comments4. Software: blog software, setup5. Data: security
Dee’s Challenge
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• Basic hardware categories: (IPOS)– Input
• Keyboard, mouse, document scanners, bar-code scanners, microphones, magnetic ink readers
– Processing• CPU – “the brain”• Main memory and cache memory• Special function cards
– Output• Video displays, printers, audio speakers, overhead
projectors, plotters– Storage
• Magnetic disks, optical disks, magnetic tapes
Q1: What Does a Manager Need to Know About Computer
Hardware?
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• Binary digits (bits)– Used to represent data
• Bit is either zero or one
• Sizing Computer Data– Bytes– 8-bit chunk equals 1 byte– Size of main memory, storage devices etc.
Computer Data
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• Internet Addressing
• Data Representation - ASCII (American Standard Coding for
Information Interchange)
Computer Data (cont.)
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ASCII Representation
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Character Code Character Code Character Code
0 00110001 a 01100001 n 01101110
1 00110010 b 01100010 o 01101111
2 00110011 c 01100011 p 01110000
3 00110100 d 01100100 q 01110001
4 00110101 e 01100101 r 01110010
5 00110110 f 01100110 s 01110011
6 00110111 g 01100111 t 01110100
7 00111000 h 01101000 u 01110101
8 00111001 i 01101001 v 01110110
9 00111010 j 01101010 w 01110111
k 01101011 x 01111000
l 01101100 y 01111001
m 01101101 z 01111010
• Kilobyte (KB or K or Kilo) – about 1 thousand or
210 (1024)• Megabyte (MB or M or Meg) – about 1 million bytes or
220 (1,048,576)• Gigabyte (GB or Gig) – about 1 billion bytes or
230 (1,073,741,824)• Terabyte (TB or Tera) – about 1 trillion bytes or
240 (1,099,511,627,776)• Petabyte (PB) – about 1 quadrillion bytes or
250 (1,125,899,906,842,624)
Capacity/Performance
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Computer Components
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• Main memory is too small to hold all programs and data
• CPU loads programs from memory in chunks– Places new program into unused memory– If none available, the operating system will
remove chunk being used and replace with requested data (Swap Files)
– It does slow down your computer
Memory Swapping
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• Main memory size– Too little means constant memory swapping
• Slows processing
• CPU speed– Expressed in hertz (Hz)– Dual core processors for PCs– Quad core processors for servers
Why Should a Manager Care How a Computer Works?
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Multi-Core Processor
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• Cache and main memory are “volatile”– Contents lost when power is cut off
• Magnetic and optical disks are “nonvolatile”– Saved contents survive after power is turned off
Why Should a Manager Care How a Computer Works? (cont’d)
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• Client computers are used for word processing, spreadsheets, database access– Connect to servers for Web, email, database
• Servers provide service to clients– They are faster, larger, more powerful– Usually have very simple video display, if any
• Server farm– Large collection of coordinated servers– Google has several hundred thousand servers in 36 data
centers around world
Q2: What’s the Difference Between a Client and a Server?
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• Grid computing– Network of computers operating as if it is one computer– Companies lease time on grid from IBM and others– Used for intensive arithmetic computing
• Cloud computing– Computing networks provided as a service on Internet
What’s the Difference Between a Client and Server? (cont’d)
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Client and Server Models
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• Thin client– Requires nothing more than browser– Does not require installation and administration
of client software
• Thick client– Has more code to run on it– More features and functions– More expense and administration
What Is the Difference Between a Thin and Thick Client?
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Hardware and Software
Cont.
Chapter 4
• Two fundamental types:1. Operating system
• Large, complex program that controls computer’s resources
2. Application programs• Perform specific user tasks
• Software constraints– Operating systems
• Run only on particular types of hardware• Must conform to instruction set of CPU• Windows works only on Intel instruction set CPUs
– Application programs • Written to use particular operating system
Q3: What Does a Manager Need to Know about Software?
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1. Windows – Used by 85% of the world’s desktops – 95% of business users– Different versions for client computers and servers, Web
sites, email, and so on
2. Mac OS– Apple Computer, Inc. developed for Macintosh computers– Easy-to-use interfaces– Used extensively by graphic artists and art community– Runs on PowerPC processor or a MAC with Intel
processor
What Are the Four Major Operating Systems?
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3.Unix– Workhorse for scientific and engineering communities– More difficult to use than Windows or MAC– Not for business users (????)
4.Linux– Developed by open-source community (Linus Torvalds)– No fee to use it– IBM has developed business systems solutions that use
Linux
What Are the Four Major Operating Systems? (cont’d)
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• Application Software– Programs that perform a business function– Some are general purpose – Excel, Word– Some are specific purpose – QuickBooks, SAP
• Application Software Acquisition– Buy off-the-shelf
• May need alterations– Custom-developed software
• Tailor-made for organization
What Types Of Applications Exist and How Do Organizations Obtain Them?
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• Horizontal-market application software– Provides capabilities common across all organizations and
industries• Examples: Word, Excel, PowerPoint, Acrobat, Photoshop, Paint
Shop Pro, PageMaker• Off-the-shelf software, little or no customization
• Vertical-market application software– Serves need of specific community/industry
• Examples: appointment scheduling, tracking system for mechanics
• Can be customized by vendor or qualified consultant
What Types of Application Programs Exist?
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1. Off-the-shelf
2. Off-the-shelf with alterations
3. Custom-developed software– Difficult, risky and expensive– May be developed in-house or by outside
developer
How Do Organizations Acquire Application Software?
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Summary of Software Sources and Types
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• Computer software installed into devices– Printers, print servers, communication devices– Coded like other software– Installed into read-only memory
• Becomes part of device’s memory– Can be changed and upgraded
What Is Firmware?
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• Manager’s role depends on organization’s policies– Large organizations have IS department that sets
standards for hardware and software– Medium to small organizations less formal
• Managers take more active role
• Usually standardize to single client operating systems
• Managers and employees may have role in specifying horizontal and vertical application software
• Usually no role in specifications of server hardware• Work with technical personnel to test and accept
software
Q4: What Buying Decisions Do You Make?
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• Viruses– Computer programs that replicates themselves– Take unwanted and harmful actions– Consume computer resources
• Payload causes unwanted activity
• Trojan horses– Viruses that masquerade as useful programs or files, such
as games, MP3s, and so on
• Macro viruses– Attach to Word, Excel, and so on to infect documents– Place themselves in startup files– Infect every file the application creates or processes
Q5: What Are Viruses, Trojan Horses, and Worms
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• Worms– Viruses that propagate using Internet or network– Specifically programmed to spread– Actively use networks to spread
What Are Viruses, Trojan Horses, and Worms (cont’d)
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• Never download from unknown sites• Don’t open attachments from strangers• Don’t open unexpected attachments
• Don’t rely on file extension names• Purchase antivirus program to detect and eliminate
viruses
Prevention Steps
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Q1: What does a manager need to know about computer hardware?
Q2: What’s the difference between a client and a server?
Q3: What does a manager need to know about software?
Q4: What buying decisions do you make?
Q5: What are viruses, Trojan horses, and worms?
Active Review
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Hardware and Software
Chapter 4