Computer hadrware,software,networking,and communication

8/9/2019 Computer hadrware,software,networking,and communication

1/75

B Y : A s s t p r o f . D i p t i P u r o h i t

INFORMATION TECHNOLOGYINFRASTRUCTURE


2/75

By: Dipti Purohit

2

UNIT 2 Computer hardware

Software

Managing &OrganizationData &Information

Information networks

Internet, Intranet

I.


3/75

By: Dipti Purohit

3

COMPUTER

Understand and distinguish between mainframecomputer, network computer, personal computer,laptop, personal digital assistant (PDA) in terms ofcapacity, speed, cost, and typical users.

Main Parts of a Personal ComputerKnow the main parts of a personal computer such as:

central processing unit (CPU), hard disk, commoninput and output devices, types of memory.Understand the term peripheral device.


4/75

By: Dipti Purohit

4

1.Central Processing Unit

The Central Processing Unit or CPU can be thought of as thebrain of the computer. The function of the CPU is to execute theinstructions in the programs. At the heart of its operations arearithmetic and logical operations.

1.1. Processor Chip

The CPU is made up of millions of electronic components called transistors,

capacitors and resistors. Transistors are the active components of the CPU.Modern CPUs contain millions of transistors.


5/75

By: Dipti Purohit

5

PARTS OF CPU

1.2. Integrated Circuit It was the miniaturization of

components and the creationof the integrated circuitthat has made thedevelopment of moderncomputers possible. Although

integrated circuits containenormous numbers ofcomponents and connectors,the whole object ismanufactured as a single itemthrough special manufacturingtechniques. From the outside,

the integrated circuit looks likea small black box with anumber of electricalconnectors on the outside.


6/75

By: Dipti Purohit

6

Input devices

Input devices are components which areused to feed commands and data intothe computer. These include devices

such as keyboards and mice.


7/75

By: Dipti Purohit

7

Cont..

1. Track ball2.Barcode reader

3.Light pen

4.Joystick

5.Digital camera

6.Scanner

7.Microphones


8/75

By: Dipti Purohit

8

Output devices

Output devices are devices that thecomputer uses to send us the results ofthe processing. These include the VDU

(monitor) and printers.


9/75

By: Dipti Purohit

9

Cont.

1.PlotterPlotters are usually used in

conjunction with CAD(Computer Assisted Design)programs. These are used in

everything from the design ofships and machines to buildings.

2.Speakers

1.


10/75

By: Dipti Purohit

10

Peripheral devices

A computer system comprises the case whichhouses the motherboard, CPU, hard drives,

power supply and various other components.

Devices such as printers, monitor, keyboardmouse which are connected to the main unitby various types of cables and connectors are

called peripheral devices.


11/75

By: Dipti Purohit

11

Memory

Primary memory is thememory that isintimately associated

with the actual workingofthe computer. This

includes memory that holdsthe start-up routines as wellas the current program anddata it is working with.There are various forms of

primary memory: RAM,ROM and Cache memory.

Secondary memoryconsists of the variousdevices that are able tostore data and programseven when the power is off.

This includes devices such ashard drives, floppy drives,tape drives, CD drives andDVD drives.


12/75

By: Dipti Purohit

12

Input/output Devices

Some devices function as both input and outputdevices.

A touch screen is a special type of screen in which thescreen not only displays output but also responds to

being touched. A typical example is their use in autotellers at banks. Part of the screen containsinformation. Other parts may contain a menu. When

you touch one of the icons on the screen, the system

responds to the associated command.


13/75

By: Dipti Purohit

13

Storage Devices

Diskette, Zip disk, data cartridges,CD-ROM, internal, external hard

disk, DVD, Memory sticks


14/75

By: Dipti Purohit

14

Cont

Hard Disk

The hard disk is thecomponent that stores dataand programs even after the

computer has been switchedoff. It consists of a numberof rotating platters which arecovered with a magneticfilm. Information is storedusing the magneticproperties of the film. Theplatters rotate from between5000 and 8000 rpm orfaster.


15/75

By: Dipti Purohit

15

SOFTWARE

Software is divided into two broadcategories: systems software and

application software.


16/75

By: Dipti Purohit

16

TWO TYPES OF SOFTWARE

Systems software is the term used to

described programs thatenable the computer tofunction, improve its

performance and access thefunctionality of thehardware. Systems softwaresole function is the control ofthe operation of thecomputer. You can think ofsystems software asproviding the foundation forapplications software.

Applications software is the term used for

programs that enablethe user to achievespecific objectives such as

create a document, use adatabase, produce aspreadsheet or design a

building.


17/75

By: Dipti Purohit

17

Operating System Software

The following is a list of some of the functions of the operating system:

Boot-up the computer. Control the hard drives: This includes such features as formatting and

defragmenting

disks as well as saving files to and retrieving files from disk. Control input devices such as keyboards, mice and scanners. Control output devices such as the video display and printer. Control the external ports: Ports are the external connections that enable

peripheraldevices to be connected to a computer. Common types of ports are serial,

parallel, USB and firewire. Of these the USB ports are the most important. Provide the functionality for computers to be linked in a network. Provide the foundation for application software to be launched. Enable application software to access and use the hardware.


18/75

By: Dipti Purohit

18

Some operating systems

Unix; Linux; Free BSD Windows 95; Windows 98; Windows Me,Windows NT4 Workstation / Server;

Windows 2000 Workstation / Server;Windows XP; Windows 2003 Server, VISTA,Windows 7


19/75

By: Dipti Purohit

19

Applications Software

some common software applications such as: wordprocessing, spreadsheet, database,

Web browsing, desktop publishing, accounting, etc.


20/75

By: Dipti Purohit

20Application Brand name function Word processor OpenOffice.org

WriterStarWriter,KWordMicrosoft WordLotus Ami ProCorelWordPerfect

Create, store, format and edit documents,letters andarticles. Word processors are used wherethe emphasis ison manipulation of text.

Spreadsheet SpreadsheetOpenOffice.orgCalcStarCalc,KSpreadMicrosoft ExcelQuattro ProLotus 123

Create financial statements, balancesheets, performstatistical and numerical analysis of data,make forecastsbased on numeric data. Spreadsheets areused where theemphasis is on arithmetic.

Presentation OpenOffice.orgImpressStarImpressKPresenterMicrosoftPowerPoint

Create slide shows, lectures, seminars andother types ofpresentation.Database Sybase, MySQL

Microsoft AccessStore and convert data into information.Databases areparticularly useful in working with largequantities ofdata.


21/75

By: Dipti Purohit

21

Application Brand name Function

Emailclient

Evolution, KMailMicrosoft

Outlook

Send, receive, store and organiseelectronic mail.

WebBrowser

Mozilla, NetscapeMicrosoft InternetExplorer

Surf the Internet and view web sites.

Desktoppublishing

DTP

MicrosoftPublisher

Page Maker

DTP is similar to word processing exceptthat there is

more emphasis on page layout and theintegration ofdiagrams.

Accounting GnuCashPastel Accounting

Store accounting information and producereports,statements and invoices.

WebDevelopment DreamweaverMicrosoftFrontPage

Create web sites that can be read by abrowser

GraphicsandImaging

The GIMPAdobe Photoshop

Create and manipulate graphics imagesand store imagesin a variety of formats.


22/75

By: Dipti Purohit

22

Graphical User Interface

Agraphical user interface or GUI is designed tosimplify the work of the user whether they areusing the operating system or an application package.The interface consists of a screen with a number of

icons or menus. Functions are executed by pointingand clicking with the mouse.


23/75

By: Dipti Purohit

23

Managing Information Systems

Information Systems (IS) have enormous strategic valueso when they are not working even for a short time, anorganization cannot function. Furthermore, the Life CycleCosts (acquisition, operation, security, and maintenance)

of these systems is considerable. Therefore, it is essentialto manage them properly. The planning, organizing,implementing, operating, and controlling of theinfrastructures and the organizations portfolio ofapplications must be done with great skill. The responsibility for the management of informationresources is divided between two organizational entities


24/75

By: Dipti Purohit

24

Cont

The information systems department (ISD), which is acorporate

entity the end users, who are scattered throughout theworld


25/75

By: Dipti Purohit

25

Fundamental Concepts

Database is a shared collection of related datawhich will be used to support the activities ofparticular organization. Database can be viewedas a repository of data that is defined once andthen is accessed by various users. A database hasthe following properties:

It is a representation of some aspect of the real world; orperhaps, a collection of data elements (facts) representingreal world information.

Database is logical coherent and internally consistent. Database is designed, built, and populated with data for a

specific purpose.


26/75

By: Dipti Purohit

26

Database Management System (DBMS)

Database Management System (DBMS) is acollection of programs that enable users tocreate, maintain database and control all theaccess to the database. The primary goal of the

DBMS is to provide an environment that isboth convenient and efficient for user toretrieve and store information.


27/75

By: Dipti Purohit

27

The components of a database system

Application program accesses the data stored in the database by sending requeststo the DBMS.


28/75

By: Dipti Purohit

28

File-based approach for banking system/Databaseapproach for banking system


29/75

By: Dipti Purohit

29

Classification of Database Systems

Based on the ways database is distributed we havecentralized or distributed system

1.Centralized database system : Data in this kindof system is stored at a single site.

2.Distributed database system: Actual databaseand DBMS software are distributed in various sitesconnected by a computer network.


30/75

By: Dipti Purohit

30

Centralized Database System


31/75

By: Dipti Purohit

31

Distributed Database System


32/75

By: Dipti Purohit

32

Benefits of Database Approach

1. To control Data Redundancyo In the Database approach, ideally each data item is stored in only oneplace in the databaseo However, in some case redundancy is still exists to improving systemperformance, but such redundancy is controlled and kept to minimum

2 Data Sharingo The integration of the whole data in an organization leads to the ability toproduce more information from a given amount of data3 Enforcing Integrity Constraintso DBMSs should provide capabilities to define and enforce certainconstraints such as data type, data uniqueness.4 Restricting Unauthorized Accesso Not all users of the system have the same accessing privileges.o DBMSs should provide a security subsystem to create and control the useraccounts.


33/75

By: Dipti Purohit

33

Information Networks

A set of computers connected together so that they cancommunicate is called a computer network. This involvesinstalling network cards in each computer. Eachcomputer is then connected through cabling to a centraldevice called a hub. Operating systems contain

components that are dedicated to the task of enablingcomputers to communicate over a network. This softwaremakes use of special rules of communication calledprotocols. There are many different types of protocolsused for a variety of purposes. The most commonly usedprotocol for establishing and maintaining communication

across a network is called TCP/IP or TransmissionControl Protocol / Internet Protocol.


34/75

By: Dipti Purohit

34

Telecommunications Network Model

A telecommunications network is any arrangementwhere Asender transmits a message

To a receiver

Over a channel Consisting of some sort ofmedium


35/75

By: Dipti Purohit

35

Telecommunications NetworkComponents

Terminals Any input/output device that uses networks

to transmit or receive data

Telecommunications processors Devices that support data transmission, reception

Telecommunications channels Media over which data are transmitted, received

Computers All sizes and types

T l i i N k


36/75

By: Dipti Purohit

36

Telecommunications NetworkComponents

Telecommunications control software Controls telecommunications activities

Manages the functions of telecommunications networks

Includes network management programs of allkinds Telecommunications monitors (mainframes)

Network operating systems (network servers)

Web browsers (microcomputers)


37/75

By: Dipti Purohit

37

Network Component Alternatives


38/75

By: Dipti Purohit

38

Types of Communications Networks

Primary types of communications networks Wide Area

Local Area Virtual Private

Client/Server

Peer-to-peer


39/75

By: Dipti Purohit

39

Wide Area Network (WAN)

Telecommunication network that covers a largegeographic area


40/75

By: Dipti Purohit

40

Local Area Network (LAN)

Connectscomputers

within alimited

physical area,such as anoffice,classroom, or

building


41/75

By: Dipti Purohit

41

Virtual Private Networks (VPN)

Used to establish secure intranets and extranets The Internet is the main backbone network

Relies on network firewalls, encryption, andother security features to build a pipe through the Internet

Creates a private network without the highcost of a separate proprietary connection


42/75

By: Dipti Purohit

42

Virtual Private Network


43/75

By: Dipti Purohit

43

Client/Server Networks

Clients End user personal computers or networked computers

Servers Used to manage the networks

Processing Shared between the clients and servers

Sometimes called a two-tier architecture

Larger computer systems are being replaced with

multiple client/server networks


44/75

By: Dipti Purohit

44

Client/Server Network


45/75

By: Dipti Purohit

45

Network Computing

Networks are the central computing resource of theorganization Thin clients provide a browser-based user interface for

processing applets

Thin clients include Network computers

Net PCs

Other low-cost network devices orinformation appliances


46/75

By: Dipti Purohit

46

Network Computing

Application and database servers provide The operating system

Application software

Applets

Databases Database management software

Sometimes called a three-tier client/servermodel because it consists of

Thin clients Application servers

Database servers


47/75

By: Dipti Purohit

47

Network Computing


48/75

By: Dipti Purohit

48

Peer-to-Peer Networks

Central Server Architecture P2P file-sharing software connects all PCs

to a central server

When a PC requests a file, the server searchesall active peers on the network

The server sends the requesting PC a list oflinks to all active peers who have the file

Clicking a link connects the two PCs and automaticallytransfers the file to therequesting PC


49/75

By: Dipti Purohit

49

Peer-to-Peer Networks

Pure Peer-to-Peer Architecture No central directory or server

File-sharing software connects one PC toanother online user

When you request a file, the software searches every onlineuser and sends you a list of active file names

Clicking a link automatically transfers the file from thatusers hard drive to yours


50/75

By: Dipti Purohit

50

Central Server Peer-to-Peer Networks

Advantages Can better protect the integrity and security

of the content and users of the network

Disadvantages Directory server can be slowed or overwhelmed by too many

users or technical problems


51/75

By: Dipti Purohit

51

Peer-to-Peer Network Diagrams


52/75

By: Dipti Purohit

52

Digital and Analog Signals

Analog or digital refers to the method used toconvert information into an electrical signal Analog: an electrical current is generated that

is proportional to the quantity being observed

Digital: the quantity being observed is expressed as anumber Analog: if the temperature is 83 degrees, a measuring device

would generate 8.3 volts

Digital: a measurement of 83 degrees would be displayed as

the number 83


53/75

By: Dipti Purohit

53Telecommunications Media

Twisted-Pair Wire Ordinary telephone wire Copper wire is twisted

into pairsCoaxial Cable

Sturdy copper oraluminum wire wrappedwith spacers to insulateand protect it

Fiber-Optic Cable

One or more hair-thinfilaments of glassfiber wrapped in aprotective jacket


54/75

By: Dipti Purohit

54

The Problem of The Last Mile

Network providers use fiber optic cable as acommunications backbone Houses connected to the backbone are wired

with twisted pair

Users dont benefit from the faster, better technology


55/75

By: Dipti Purohit

55

Wireless Technologies

Terrestrial Microwave Earthbound microwave systems transmit

high-speed radio signals Follows a line-of-sight path between relay systems

spaced about 30 miles apart

Communications Satellites Serve as relay stations Use microwave radio signals Earth stations beam signals to the satellites Not suitable for interactive, real-time processing


56/75

By: Dipti Purohit

56

Wireless Technologies

Cellular and PCS Telephone and Pager Systems Geographic areas are divided into cells Each cell has a low-power transmitter or radio relay

antenna Computers and other communications processors

coordinate and control the transmissions to and

from mobile usersWireless LANS

Uses wireless radio-wave technology toconnect PCs within an office or a building

Can be high-frequency, similar to digital

cellular, or low frequency (spread spectrum)


57/75

By: Dipti Purohit

57

Wireless TechnologiesBluetooth

Short-range wireless technology Connects PCs to devices, such as a printer Fairly low cost to implement

Other Wireless Systems Cellular phones Mobile radio PDAs

Telecommunications networks now play vital and pervasiveroles inWeb-enabled e-business processes

Electronic commerce Enterprise collaboration Other applications that support business operations,

management, and strategic objectives


58/75

By: Dipti Purohit

58

The Wireless Web

Wireless Internet access is growing as Web-enabledinformation appliances proliferate Smart telephones, pagers, PDAs

All are very thin clients in wireless networks


59/75

By: Dipti Purohit

59

Telecommunications Processors

Modems The most common type of communications processor

Converts a digital signal to an analog frequency that can betransmitted over phone lines, then back into a digital signal

Modulation and demodulation


60/75

By: Dipti Purohit

60

Inter-Network Processors

Switch makes connections betweentelecommunications circuits in a network

Router intelligent communications processorthat interconnects networks based on different

protocolsHub a port-switching communications processor

Gateway connects networks with differentcommunications architectures


61/75

INTERNET INTRANET EXTRANET


62/75

By: Dipti Purohit

62

The internet is thecollection of all computersacross the world which can

access each otherin some way. The linksbetween computers mightinclude telephone, fiber opticcable,radio, microwave or satellite.Today tens of millions of

computers are able to accesseach other. The Internet hasno central organization whichcontrols its use. Because theInternet knows no borders,many governments have triedto control the flow of

information across theInternet. However,communications technology isso varied and so widespreadthat this is a near impossible

task.

An intranet is similar to theInternet in operation.However, it is limited to anorganization.

Users may browse computerswithin an intranet using abrowser but will usually not beable to access the widerInternet. In the same way,outsiders will not be able toaccess the

intranet of an organization. Anintranet can be thought of as aprivate Internet.

An extranet is anextension of aorganization's intranet toinclude outside users. Inanextranet, outsideorganizations or individualsare allowed access to certainparts of theintranet. This access is usuallycontrolled by means ofpasswords and access rights.Theserestrict which users can accessthe extranet and what they cando once they have access.The purpose of the extranet isto facilitate businesstransactions with otherorganizations.


63/75

By: Dipti Purohit

63

The Internet Revolution

The Internet has become a global informationsuperhighway Millions of smaller, private networks operating independent

of, or in harmony with, each other

10 servers in 1991 to over 46 million today

Sustained growth in excess of 1 million servers per month

No central computer system

No governing body

Based on common standards


64/75

By: Dipti Purohit

64

Internet Service Providers

ISP A company that specializes in providing easy access to the

Internet

For a monthly fee, provides software, user name, password,and Internet access

ISPs themselves are connected to one anotherthrough network access points One ISP can easily connect to another to obtain addresses of

websites or user nodes


65/75

By: Dipti Purohit

65Internet Applications

Most popular Internet applications and uses E-mail

Instant messaging

Browsing the Web

Newsgroups Chat rooms

Publish opinions, subject matter, creative work

Buy and sell

Downloading (data, software, reports, pictures, music,videos)


66/75

By: Dipti Purohit

66

Business Use of the Internet


67/75

By: Dipti Purohit

67Business Value of the Internet


68/75

By: Dipti Purohit

68The Role of Intranets

Many companies have sophisticated and widespreadintranets, offering Detailed data retrieval

Collaboration

Personalized customer profiles Links to the Internet

Intranets use Internet technologies Web browsers and servers

TCP/IP network protocols HTML publishing and databases


69/75

By: Dipti Purohit

69

Intranets

Intranets are protected by Passwords

Encryption

Firewalls

Customers, suppliers, and other business partners canaccess an intranet via extranet links


70/75

By: Dipti Purohit

70

Business Value of Intranets

Intranets support Communications and collaboration

Business operations and management

Web publishing

Intranet portal management


71/75

By: Dipti Purohit

71

Intranets as Information Portals


72/75

By: Dipti Purohit

72Extranets

Network links that use Internet technologies toconnect the intranet of a business to the intranetsof another

Virtual Private Networks Direct private network links, or private secure Internet links

between companies

Unsecured Extranet Link between a company and others via the Internet, relying

on encryption of sensitive data and firewall securitysystems

C i i


73/75

By: Dipti Purohit

73

Extranet Connectivity


74/75

By: Dipti Purohit

74Business Value of Extranets

Web browser technology makes customer and supplieraccess to intranets easier and faster

Another way to build and strengthen strategicrelationships

Enables and improves collaboration between abusiness, customers, and partners

Facilitates online, interactive product development andmarketing


75/75

75

THANK

YOU

Documents

Computer hadrware,software,networking,and communication