Case mis ch04

Hardware and Software

4장

• Dee needs information system to support

her blog

– She must calculate costs to get approval

• Needs to consider five components of

information systems 1. People: sales force and herself

2. Procedures: for posting, accessing blog, leaving

comments

3. Hardware: server

4. Software: blog software, setup

5. Data: security

Dee’s Challenge

4-2

• 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

What Does a Manager Need to Know About Computer Hardware?

4-3

What a Manager Needs to Know

About Hardware (cont’d)

4-4

Figure 4-1

What a Manager Needs to Know

About Hardware (cont’d)

4-5

• 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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Computer Components

4-7

• CPU (central processing unit)

– Transfers program or data from disk to main memory

– Moves instruction from main memory via data channel or

bus

– Has small amount of fast memory called cache

• Keeps frequently used instructions

• Large cache makes computer fast, but is expensive

• Main memory

– Contains program instructions

– Contains operating system instructions

How Does a Computer Work?

4-8

• Operating system (OS)

– Program that controls computer’s

resources and blocks of data

– Provides services to application programs

and users

How Does a Computer Work?

(cont’d)

4-9

• Why? 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

– It does slow down your computer

Memory Swapping

4-10

• Main memory size

– Too little means constant memory swapping • Slows processing

• Need more memory if processing many programs or large files

• CPU speed

– Expressed in hertz (Hz)

– Needs more CPU if handling large spreadsheets or database files

– Dual core processors for PCs

– Quad core processors for servers

Why Should a Manager Care How a Computer Works?

4-11

• 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)

4-12

• 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

What’s the Difference Between a

Client and a Server?

4-13

Figure 4-8

Client and Server Computers

4-14

• 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

– See www-03.ibm.com/grid

• Cloud computing

– Computing networks provided as a service on Internet

– Example: Facebook and others

What’s the Difference Between a

Client and Server? (cont’d)

4-15

• 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

What Does a Manager Need to Know

about Software?

4-16

What a Manager Needs to Know

about Software

4-17

Figure 4-9

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 (click)

– Apple Computer, Inc. developed for Macintosh computers

– Easy-to-use interfaces

– Used primarily by graphic artists and art community

– Runs on PowerPC processor or a MAC with Intel

processor

What Are the Four Major Operating

Systems?

4-18

1.Unix – Workhorse for scientific and engineering communities

– More difficult to use than Windows or MAC

– Not for business users

2.Linux – Developed by open-source community

– No fee to use it

– IBM has developed business systems solutions that use

Linux

What Are the Four Major Operating

Systems? (cont’d)

4-19

• Application Software – Programs that perform a business function – Some are general purpose – Excel, Word – Some are specific purpose – QuickBooks

• Application Software Acquisition

– Buy off-the-shelf • May not be a good fit • May need alterations

– Custom-developed software • Tailor-made for organization

What Types Of Applications Exist and How

Do Organizations Obtain Them?

4-20

• 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?

4-21

Thin and Thick Clients

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Figure 4-11

• 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 application software

• Usually no role in specifications of server hardware

• Work with technical personnel to test and accept

software

What Buying Decisions Do You Make?

4-23

Business Manager’s Role in Hardware and

Software Specifications

4-24

Figure 4-12

• 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

What Are Viruses, Trojan Horses, and

Worms

4-25

• Worms

– Viruses that propagate using Internet or network

– Specifically programmed to spread

– Actively use networks to spread

• Prevention

– Patches • Vendor-provided security fixes for programs

• Automatic updates or regular checks for patches

What Are Viruses, Trojan Horses, and

Worms (cont’d)

4-26

• Technology continues to change

• If you don’t keep up, you might not gain a competitive advantage

– Managers need to understand what technology is needed

• Don’t depend solely on experts

– Develop a competitive advantage in non-technology areas to compensate

• Other extreme are the “technophiles”

Guide: Keeping up to Speed

4-27

• What can a manager do? 1. Don’t ignore technology

2. Take seminars

3. Read articles, ads • C/NET, CIO.com

• Wall Street Journal technology articles

4. Attend professional events

5. Get involved as a user representative in

technology committees

Guide: Keeping Up to Speed (cont’d)

4-28

• Reduces the work and costs of her consultant

• Dee more confident in dealing with IT department

and consultant

• Better able to understand consultant’s questions and

IT department’s concerns

• Can determine: – No new client hardware needed – Use thin client on sales rep computers – Prefer thin client on her computer – Blog server software must be installed on server – IT department will decide whether to run Linux or Windows

• Then blog software will be chosen

– Set up to be performed by either IT department or consultant – Needs program to author HTML

How Does the Knowledge in This

Chapter Help Dee and You?

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