chapter 4 laudon

7/30/2019 Chapter 4 Laudon

http://slidepdf.com/reader/full/chapter-4-laudon 1/87

4.1 Copyright © 2011 Pearson Education, Inc. publishing as Prentice Hall

4 Chapter

IT Infrastructure:Hardware and Software




IT Infrastructure

• IT infrastructure: provides platform for supporting all

information systems in the business

• Computer hardware

• Computer software

• Data management technology

• Networking andtelecommunications technology

• Technology services

IT Infrastructure Components

Essentials of Management Information SystemsChapter 4 IT Infrastructure: Hardware and Software




Defining a Computer

Hardware –

– consists of the physical devices associated with acomputer system

– technology for processing, data storage, input & output

Computer -

– Machine that accepts data as input

– Processes data without human intervention usingstored instructions

– Outputs information




Defining a Computer

Hardware components include:

•Central processing unit (CPU)

•Primary storage•Secondary storage

•Input devices

•Output devices

•Communication devices




Representing Data

Binary or Machine Language

• The language that all computers use

• Expressed in 0s or 1s only

• Binary utilizes Base-2 math to convert from normalcharacters to binary code (e.g. A = 0100 0001 inbinary)

• Bit (binary digit) – a single 0 or 1, the smallest unit of

information that a computer can process• Byte – a group of 8 bits representing one natural

language character




Representing Data

Types of Binary Coding

• 8 bit coding schemes:

– ASCII

– EBCIDIC

• 16 bit coding schemes:

– Unicode


http://slidepdf.com/reader/full/chapter-4-laudon 7/874.7 Copyright © 2011 Pearson Education, Inc. publishing as Prentice Hall

Processing HW: Central Processing Unit

• Central processing unit (CPU) (or

microprocessor) - the actual hardware that

interprets and executes the program (SW)

instructions and coordinates how all the otherhardware devices work together

– Control unit

– Arithmetic-logic unit (ALU)

– Registers

– L1 (Internal) Cache Memory




– Control unit - interprets software instructions and

literally tells the other hardware devices what to do,

based on the software instructions – Arithmetic-logic unit (ALU) - performs

• all arithmetic operations (for example, addition and

subtraction)

• logical operations (such as sorting and comparingnumbers)

• storage and retrieval operations




– Registers - provide temporary storage where data

resides while it is being processed or manipulated

– L1 (Internal) Cache Memory - a small block of memory used by the processors to store those

instructions used most recently or most often

• incorporated into the microprocessor’s design, right

on the CPU chip



Processing Issue: Speed

Speed – how fast can we process an instruction?

Measured in fractions of a second:

– Micro- (1 millionth) .000001

– Nano- (1 billionth) .000000001

– Pico- (1 trillionth) .000000000001

– Femto - (1 quadrillionth).000000000000001

– Atto - (1 quintillionth) .000000000000000001

– Zepto - (1 sextillionth .000000000000000000001

– Yocto-(1 septillionth) .000000000000000000000001



Processing – Performance Factors

• Clock Speed – the speed of the internal clock

(system clock) that sets the pace at which

operations proceed; clock speed is measured in

hertz (MHZ, GHZ)

• Word length – the number of bits that can be

processed by the CPU at one time: 32 bit vs.

64 bit




• Bus – the link between devices connected to

the computer

– Internal or External

– Serial or Parallel

• Bus width – the size of the electrical pathway

along which signals are sent from one part of

the computer to another




• Processor configuration -

– Single processor

– Multiple processors aka “co- processor” – Multicore processor – an integrated circuitwith multiple cores/processors attached(dual core, quad-core, etc)

• Enhanced performance

• Reduced power consumption



Evolution of Processing Technology

The History of Computer Hardware



• Personal digital assistant (PDA), smartphones,

e-readers

• Tablet

• Netbook, Laptop

• Desktop

• Workstation

• Minicomputer

• Mainframe computer

• Server • Supercomputer

• Grid Computing

Types of Computers




• Servers:

• Often a type of midrange computer.

• Support computer network, sharing files and resources.

• Provide hardware platform for e-commerce.

• Types of Servers:

• Application Print

• Database Remote access (RAS)• Disk Web

• Fax File

• Mail

Types of Computers




Supercomputer:

• More sophisticated computer used for tasks requiring extremely

rapid and complex calculations with thousands of variables,

millions of measurements• Used in engineering, scientific simulations, military/weapons

research, weather forecasting

• Utilize parallel processing – the ability to run two or more tasks

simultaneously by using multiple processors linked to operate

together

• http://www.top500.org/lists/2012/06

Types of Computers


http://www.top500.org/lists/2012/06

http://www.top500.org/lists/2012/06



Grid computing:

• Power of geographically remote computers connected into single

network to act as “virtual supercomputer”

• Connecting different computers to combine their processing power to

solve a particular problem

• Each participant in a grid is called a “node”

• Advantages:

• Cost savings

• Speed of computation

• Improved reliability - processing on overused nodes can be

switched to idle nodes

• Scalability

Types of Computers





Three Basic Types:

• Centralized – processing is done by one large central

computer • Decentralized – each user, department, division has its own

computer for processing

• Distributed – processing power is distributed among several

locations; multiple computers are linked by a communicationsnetwork for processing

Processing Configurations





Client/server computing:

• Form of distributed computing

• Splits processing between “clients” and “servers” – each type

assigned certain functions

• Clients: user point of entry; requests services from a server

• Servers: store and process shared data and perform networkmanagement activities in response to client requests

• Servers may be dedicated to special functions (slide 17)






Two-tiered client/server architecture - uses two types of

machines – a client computer networked to a server computer






N-tier or Multitiered client/server architecture

• Balances load of network over several levels of servers (E.g.

Web servers and application servers)






Storage HW: Memory Devices

• Storage Capacity – how much can we store?




Storage HW: Memory Devices

• Main memory

– Semi-conductor memory chips

– Consists of RAM, ROM and L2 Cache that is directly

accessible to the CPU• Secondary memory

– Nonvolatile

– Holds data when the computer is off or during course

of a program's operation – Serves as archival storage

– Various types




Main Memory: Random Access Memory (RAM)

• Random access memory (RAM) - the computer’s

primary working memory; used to store program

instructions & data that can be accessed directly by the

CPU via the processor’s high-speed data bus – Provides temporary storage for computer operations

– Stores programs and data currently in use

– CPU can randomly access the data stored in RAM

– Instructions are considered volatile and will be lost when thecomputer is turned off

– Individual RAM chips, SIMM, DIMM




Main Memory: L2 Cache

• Cache memory - a type of high-speed

memory that the CPU can access more rapidly

than main memory (RAM); used to store

recently accessed or frequently accessed dataand instructions

– L2 (External) cache is a separate chip that is

located on the motherboard very close to the CPUfor easy access




Main Memory: Read-Only Memory (ROM)

• Read-only memory (ROM)

• Nonvolatile (does not lose its contents when

one switches off the power)

• Stores permanent control instructions: “boot

up” commands – BIOS and the system

clock

• Other forms: PROM, EPROM




Secondary Memory/Storage

• Secondary memory/storage - consists of equipmentdesigned to store large volumes of data for long-termstorage

• Nonvolatile - is used to permanently storeinformation; comes in many types

• Offers greater capacity & greater economy

• Issues:

– Access method – Storage capacities

– Portability

– Cost




Storage Access Methods

• Sequential: records must be retrieved in order

– Devices used are called sequential access storage

devices (SASD)

• Direct: records can be retrieved in any order –

also called Random Access

– Devices used are called direct access storage

devices (DASD) – Each storage location has a unique address




Exhibit 2.3 Examples of Secondary Storage Devices




Secondary Storage Choices: Magnetic Tape

Magnetic Tape

– Plastic (mylar) tape on which data is stored

in form of magnetized spots (bits)

– Sequential access only

– Commonly used for back up or storing

archival data




Secondary Storage Choices: Magnetic Disks

• Magnetic Disks

• Direct (random) or sequential access

• Data is stored in form of magnetized spots (bits)

• Fast data retrieval for individual data items• Each storage location has a unique address identifying the

track and sector

• Disks with multiple platters also need to know which platter

and which side of the platter the data is stored on• Issues

• Capacity

• Portability

• Access time




Secondary Storage Choices: Magnetic Disks

• Types of Magnetic Disks• Hard Disks – can be internal or external

• Floppy diskettes• ZIP

• RAID (Redundant Array of Independent Disks)




Secondary Storage Choices: Optical Discs

Uses a laser to: write by burning spots into a diskcoated with a metallic substance; read byinterpreting the reflection of the light off theburned-in data spots

– Compact Disk (CD) – original form of opticaldata storage

• CD-ROM (read only); CD-R (write once); CD-RW(can re-write)

– Digital Video Disk (DVD) – optical storageformat used for movies & other video media butcan also be used for data storage; holds over 7times or more a CD’s capacity

• DVD DVD-R DVD-RW Blu-ray




Secondary Storage Choices: Flash Media

• Flash Memory – a special type of semi-

conductor memory that is portable, non-

volatile and can be electronically erased &

rewritten to – Flash Drives/Jump Drives/USB Drives

– Memory cards or memory sticks – high capacity semi-

conductor storage that holds data such as captured images,

music or text files for a variety of portable devices

including computers, digital cameras, MP3 players, PDAs,

gaming systems

T bl 2 4




Capacity of Secondary Memory Devices

Table 2.4




Secondary Storage: Storage Networking

• SAN – Storage area network

• A dedicated high-speed network used to

connect & manage shared storage devices of

different types

– Speeds up data access

– Easy to add to

– Can integrate different types of storage




Secondary Storage: SAN

Essentials of Management Information Systems




A Storage Area Network (SAN)

Secondary Storage: SAN

Figure 4-4

A typical SAN consists of aserver, storage devices,and networking devices,and is used strictly for

storage. The SAN storesdata on many differenttypes of storage devices,providing data to theenterprise. The SANsupports communication

between any server and thestorage unit as well asbetween different storagedevices in the network.





• Type/format of data – text, numbers, audio,images, video

• Data - can be human or machine readable

• 2 Step Process

– Data entry - converts human readable data into

machine-readable form

– Data input - transfers the machine-readable datainto the system

• Traditional data entry methods …

Input Hardware




Input HW: Text & Numbers

• Primary device is keyboard – each key has its

own digital code

• Converts human readable data into machine

readable format and transfers it to the system




Input HW Issue: Ergonomics

• Ergonomics – the study of designing & positioningcomputer equipment for employee health & safety

• Health Concerns – Stress & anxiety

– Repetitive stress injury (RSI) – Repetitive motion disorders

– Carpal tunnel syndrome (CTS)

– Eye strain

– Harmful emissions from monitors, cell phones, laserprinters, etc.

• http://datahand.com/overview/photos.htm • www.footmouse.com/

http://datahand.com/overview/photos.htm

http://www.footmouse.com/

http://www.footmouse.com/

http://datahand.com/overview/photos.htm




Input HW: Pointing & Selecting Information

• Input HW that allows you to select items from

menus, to point, & to sketch or draw

– Mouse

– Joystick

– Trackball

– Touchpad

– Stylus & Light Pens

– Touch sensitive screens




• Devices used to automate the entry of data

– Handheld or Flatbed Scanners

– Optical Mark Recognition (OMR)

– Optical Character Recognition (OCR) – Bar Code Scanners

– Magnetic Ink Character Recognition (MICR)

– Smart Cards

– Cards with RFID Chips

– QR Codes

Input HW: Automated Input Devices




Radio Frequency Identification: An Overview

• Radio frequency identification (RFID) tag

– Small electronic device consisting of a small chip andan antenna

– Provides a unique identification for the card or theobject carrying the tag

– Don’t have to be in contact with the scanner to beread

– Can be read from a distance of about 20 feet




What are QR Codes?

• QR Code (Quick Response Code)

– A type of matrix barcode

– Fast readability and large storagecapacity

– Used in a wide range of applicationsincluding commercial tracking,ticketing, product marketing, and in-store product labeling

– Many applications target mobile device

users who can scan the QR Code toaccess a URL or other data

– http://searchengineland.com/what-is-a-qr-

code-and-why-do-you-need-one-27588

http://searchengineland.com/what-is-a-qr-code-and-why-do-you-need-one-27588


http://en.wikipedia.org/wiki/File:Wikipedia_mobile_en.svg



























Input HW: Entering Audio Data

• Audio HW includes microphones & speakers• Voice-recognition devices

– Involve converting human speech patterns into digital patterns

– Convenient when need “hands-free” input

– Very easy/user-friendly – Requires large storage capacity

– Still relatively slow & error prone

– Greater accuracy requires “training” the computer to recognizeindividual voice patterns

– Problems with word recognition …. • “Recognize speech/wreck a nice beach”

• “Dr. Wright will write the right prescription and you can take it toRite-Way Pharmacy …”




Input HW: Entering Audio Data

• Other Audio Input Applications:

– Internet based telephone calls (VOIP)

– Instant Messaging with voice

– On-line video gaming

– Videoconferencing

– Music




Input HW: Entering Video Data

• Video Input HW includes digital & video

cameras and players

• Business quality videoconferencing cameras &

equipment

• Web cams – lower quality & cost cams used

for Internet chatting or office-to-office

videoconferencing




• “Dumb” terminals

– Perform data entry & input at the same time

– Are connected by lines or cables to a complete

computer system• Point-of-Sale (POS) Devices

– Terminals used in retail operations to enter salesinformation into the computer system

• Both of these may incorporate other I/Odevices such as keyboards, bar code readers,OCR scanners, printers, monitors

Other Input HW Devices




• Automated Teller Machine (ATM) Devices

– Special purpose input/output device

– Incorporate other I/O devices such as keypads,

monitors, printers, credit/debit card readers,deposit slots, cash dispensers

• Brain Wave Input

– Also called a neural interface

– Uses biofeedback techniques to learn to controlcertain types of brain waves in order to cause sometype of action to occur






Brain Wave input

– http://www.youtube.com/watch?v=d55CJYtHKAI

Dasher SW (eye movement as input)

– http://www.inference.phy.cam.ac.uk/dasher/Demonstrations.ht

ml

Microsoft Surface Computing

- http://news.com.com/1606-2_3-6186146.html

Tongue Drive System -http://www.gatech.edu/newsroom/release.html?nid=110351

http://www.sciencedaily.com/videos/2008/1112-

tonguedrive_wheelchair.htm

http://www.youtube.com/watch?v=d55CJYtHKAI

http://www.inference.phy.cam.ac.uk/dasher/Demonstrations.html


http://news.com.com/1606-2_3-6186146.html

http://www.gatech.edu/newsroom/release.html?nid=110351

http://www.sciencedaily.com/videos/2008/1112-tonguedrive_wheelchair.htm





http://www.gatech.edu/newsroom/release.html?nid=110351








http://www.youtube.com/watch?v=d55CJYtHKAI




• Trends in Input HW

– More direct input

– Easy to use – Faster

– More accurate

– Fewer steps

– Less paper

Trends in Input HW




Output HW • Output may be provided in printed, digital,

visual, audio form

• Should be appropriate media choice for use

• Hard copy vs. Soft copy




• Display Monitors• Technology used to generate image

– CRT,LCD,LED, plasma

• Screen size, screen shape, colors, energy requirements

• Response time, contrast ratio, degree of viewing angle

• Resolution –

– Pixel – dot or picture element; the more pixels or dots per

square inch, or dpi, the sharper the image

– Dot pitch – the distance between one pixel & another; the

closer the pixels are together the sharper the image

• VRAM – video RAM

– Image data is put into this faster video memory to optimize

speed in getting it displayed

Output HW: Visual




Output HW: “Hard Copy”

Printers – Issues: – Speed: pages per minute

– Print quality (resolution) – the higher the dpi (dots perinch) the better the print quality

– Graphics/colors/multiple part forms – Photo input slots/photo paper tray

– Size of LCD screen for menu, commands

– Buttons vs. touch screen input

– Built-in wireless access

– “e- printing” from mobile or remote device

Plotters – produce high quality graphics; used for typesof design work




Output HW: Audio

• Voice Output – voice synthesizers

• Music Output – Speakers

– MP3 Players

Audio Audio is transmitted using a sound card inserted into oneof the motherboard’s slots and is connected to speakers.The computer translates digital code into sound bysending the data to the sound card that interprets thesedata into tones




Output HW: Scents & more …?

• Scents, Taste, Textures ? Scratch & Sniff web sites ??

• The sense of smell is closely tied to memory & emotion,making scent a powerful way to reinforce ideas.

• We are used to smells/odors informing us about the state of

things in our immediate vicinity … • Scents can be used in a symbolic way – released as cues to

signify an event or condition … – E-commerce

– Education/training

– Travel

– Games/entertainment

– Food/cooking


http://asia.cnet.com/crave/2005/04/25/scent-dome/




Contemporary Hardware Trends

• The emerging mobile digital platform

• New handheld devices like cell phones, netbooks, tablets and e-

readers now present an alternatives to PC’s and larger

computers – providing a new “platform”

• Wireless communications thru 3G/4G cell networks and Wi-Fi

• New software apps

• Nanotechnology

• Technology that builds structures and processes based on the

manipulation of individual atoms and molecules

• Creating computer chips and other devices thousands of times

smaller through manipulating individual atoms, molecules

Chapter 4 IT Infrastructure: Hardware and Software






Virtualization - Process of presenting a set of computing

resources so they can be accessed in ways that are

unrestricted by physical configuration or geographic

location

• Server virtualization: running more than one

operating system at the same time on single machine;

“acts” as if one machine is several different ones

• Reduces the number of computers required for

processing, boosts server utilization rates (improve

productivity, lower costs)







Cloud Computing:

• A model of computing in which firms and individuals obtain

computing resources over the Internet

• Includes the following characteristics

• On demand self service

• Ubiquitous network access

• Location independent resource pooling

• Rapid elasticity

• Measured service

• Public cloud vs. private cloud

• Utility (on-demand) computing – users pay for computing or

storage resources on an as-needed basis







Cloud Computing, cont.

• Different types of services:

• Cloud infrastructure as a service – co’s use processing,

storage, networking resources from cloud providers

• Cloud platform as a service – customers use infrastructure

and programming tools hosted by the vendor to develop

their own applications/software

• Cloud software as a service – SaaS – customers use SW

hosted by the vendor







• Green computing

• Practices and technologies for designing, making, using, and

disposing of computer hardware

• Key priority is power reduction

• IT in U.S. provides 2% of U.S. power demand and 2% of

world’s greenhouse gases







Autonomic computing:

• Development of systems that can configure themselves,

optimize and tune themselves, heal themselves, protect

themselves from outside intruders





Computer Software

• Software – “programs”

– the programs that run a computer system

– step by step directions for performing aspecific task

– the instructions that operate the informationsystem

– written in a language the computer canunderstand

• Classified broadly as:

– System software

– Application software

Essentials of Management Information SystemsCh t 4 IT I f t t H d d S ft




The Major Types of Software

Figure 4-7

The relationship among thesystem software, applicationsoftware, and users can beillustrated by a series of nestedboxes. System software—

consisting of operating systems,language translators, and utilityprograms—controls access to thehardware. Application software,including programminglanguages and ―fourth-

generation‖ languages, mustwork through the system softwareto operate. The user interactsprimarily with the applicationsoftware.





System Software

• System software – controls access to the

hardware; the collection of programs that control

the basic functions of computer hardware; controlshow the various technology tools work together

along with the application software

– Operating system software – Utility software

– Language translators




System Software: Operating System Software

• Operating system (OS)

– Set of programs for controlling and managingcomputer activities

– Provides an interface between a computer and theuser

• GUIs and multitouch

– Increases computer efficiency by helping users sharecomputer resources and performing repetitive tasks

for users




System Software: Utility Software

• Utility SW - provides additional functionality to theoperating system

• Types of utility software – Crash-proof

– Disk image

– Disk optimization

– Encrypt data

– File and data recovery

– Spam blockers – Virus protection

– Spyware detection

– Uninstallers




System Software: Language Translators

• Language Translators

– Set of programs for translating programs written inprogramming languages higher than machinelanguage (1st generation languages) into machinelanguage

• Assemblers

• Compilers

• Interpreters




Programming Language Translating Programs

A type of System SW -

– Assembler - SW program used to convert 2nd generation program instructions (source code) intomachine code (object code) prior to being loaded into acomputer’s secondary storage

– Compiler – SW program used to convert 3rd generationand higher program instructions (source code) intomachine code (object code) prior to being loaded into acomputer’s secondary storage

– Interpreter – SW program similar to a compiler butinstead of translating the entire source code to machinelanguage prior to executing, it reads, translates, andexecutes one line of source code at a time duringoperation




Application Software

• Application software – Can perform a variety of tasks; used for specific

information processing needs for the user

• Types

– Programming Languages

– Business Systems

– Desktop productivity tools




Application SW: Programming Languages

Programming Language -

• Set of key words, symbols and rules (syntax) for

constructing statements by which humans can

communicate instructions to be executed by acomputer

• Are used to write program instructions - have evolved

over time, making them more powerful, easier to read

and write, and more natural language-focused

• Different languages have different characteristics




Application SW: Programming Languages

• The only programming language the computerunderstands is machine language (binary code)

• All other languages must be translated back into

machine language• Programming language translating programs are a

type of systems SW

• 2nd generation languages (assembly languages) use an

assembler

• 3rd & up generation languages use a compiler or an

interpreter




First Generation Languages

• Machine languages

• Binary code (0s and 1s)

• Machine dependent

• Procedural• Most efficient for the computer




Second Generation Languages

• Assembly languages (Symbolic languages)

– Symbolic code – uses short code/acronyms

– Machine dependent

– Procedural

– Still fairly efficient for the computer

– Use an assembler (SW program) to translate back

to machine language – Used to write types of Systems Software programs




Third Generation Languages

• High-level languages – Use English-like statements & commands and standard

mathematical notation/formulas

– Procedural

– NOT machine dependent – Less efficient for the computer, more efficient for the

programmer

– Many choices

• COBOL, Fortran, Basic, C, Pascal, etc. – Use a compiler or an interpreter (SW programs) to

translate back to machine language

F th G ti L




Fourth-Generation Languages

• Fourth Generation Languages (4GLs) – Very high-level languages, more English-like, easier to

learn

– Enable end users to develop SW applications with little or

no technical assistance – NON procedural - programs tell the CPU the desired

results or outcome, not how to get them (sometimes called“outcome oriented” languages)

– NOT machine dependent

– Examples: SQL, SAS, Focus, Nomad, PowerBuilder

– Use a compiler to translate back to machine language





Categories of Fourth-Generation Languages

IT Infrastructure: Computer Software

Tool Description Example

PC software tools General-purpose software packages for

PCs

WordPerfect

Microsoft Access

Query language Languages for retrieving data stored in

databases or files

SQL

Report generator Specialized tools for creating highly

customized reports

Crystal Reports

Graphics language Display data from databases in graphic

format

SAS Graph

Systat

Application generator Preprogrammed modules to generateentire applications

WebFOCUSQuickBase

Application softwarepackage

Software programs that eliminate need

for custom, in-house software

Oracle PeopleSoft HCM

mySAP ERP





Application Software: Business Systems

• Business application SW – Financial planning and accounting

– Project management

– Computer-aided design (CAD) – HR – payroll, benefits

– Operations – inventory management, logistics

– Other functional area business systems




Application SW: Desktop Productivity Tools

Software packages that support OfficeAutomation & the daily work activities of individuals & groups

– Word Processing SW – Spreadsheet SW

– Data management SW

– Presentation graphics SW – Software Suites

– Web browsers





Software for the Web:• Java

• HTML (Hypertext markup language)

• HTML5

Web Services

• XML (Extensible markup language)

Software for the Web & Web Services

C apte ast uctu e a d a e a d So t a e





Software for the Web & Web Services

p





• Open Source Software – source code is

available so anyone can make changes – to fix

errors or make improvements

• Linux, Apache

• Cloud Computing – cloud based SW & tools

• Software as a Service (SaaS)

• Google Apps, Office Web Apps

Software Trends

p





• Mashups – SW composed ofinterchangeable components that mix freelywith other applications

• Mix and match to create your owncustomized applications

• Apps – small pieces of SW that run on theInternet, on your computer or on your

mobile phone or other device

• Games, music, social networking, news,weather, maps, etc.

Software Trends

p




Managing HW and SW Technology

• Capacity planning

• Determining Costs – Total Cost ofOwnership

• Using Technology Service Providers

• Outsourcing

• Using Cloud Services

• Managing SW localization for globalbusiness

p

chapter 4 laudon

Documents