The document introduces computer networks and their applications. It defines a computer network as an interconnection of computers that allows users to share information and resources. The document outlines the objectives of the chapter which are to explain the concept, need, types and applications of computer networks as well as the workings of the Internet and email. It then proceeds to describe client-server and peer-to-peer network models, different types of networks based on geographical coverage, and applications of networks including the Internet, email and financial services.

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Introduction to
Computer Networks
Chapter 1
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Chapter Objectives
 Explain the concept of a computer network
 Explain the need of a computer network
 Define the various types of network
 Explain different applications of a computer
network
 Define and explain the working of the Internet
 Explain about email
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Computer Network
 Interconnection of two or more computers and
peripherals
 Allows user to share and transfer information
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Need of Computer Networks
 Sharing Files, folders, data and information
 Sharing hardware resources such as a
network printer
 Sharing software, as many users connected
to the network can run the same application
program
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5. Types of Network Configuration
 Client-Server Model
 Peer-to-Peer Model
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6. Question for GD Time Limit – 3 Mins
 What are the needs of a computer network?
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7. Client Server Model
 Is a configuration of the computer network that includes
a server and one or more clients.
 Client manages the local resources that are used by the
user such as monitor, keyboard, CPU and peripherals.
 Server is a more powerful system which manages
shared resources such as databases, printers,
communication links and handles all the incoming
requests for its shared resources.
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8. Peer to Peer Model
 A communications model in which each party has the
same capabilities and either party can initiate a
communication session.
 In recent usage, peer-to-peer has come to describe
applications in which users can use the Internet to
exchange files with each other directly.
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Types of Computer Networks
 Networks are classified depending on the
geographical area covered by the network
Computer
Networks
Local
Area Network
(LAN)
Campus
Area Network
(CAN)
Metropolitan
Area Network
(MAN)
Wide
Area Network
(WAN)
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10. Question for GD Time Limit – 3 Mins
 Name the different types of network
configuration.
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Local Area Network (LAN)
 Covers a small area
 Connects computers and workstations covering a
local area like, office or home
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Metropolitan Area Network
 Interconnects networks within a city
 Supports data and voice transmission
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Wide Area Network
 Covers a wide geographical area which includes
multiple computers or LANs e.g. Internet
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14. Difference between LAN and WAN
LAN WAN
Connects computers and workstations in office
or home
Connects geographically separated LANs
Covers a local area of 1 Km. Spans large geographical area more than 100
Km.
Data Transmission Rate – 10/100/1000 Mbps Data Transmission Rate – 64 Kbps to 10 Mbps
Follows IEEE 802 standard Follows ITU standard
Low cost High cost (Repetitive)
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15. Question for GD Time Limit – 3 Mins
 List the different types of computer networks.
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Network Applications
 Financial Institution (Banking Sector)
 Communication Services (Telecom Industry)
 Internet Service (WWW, ISP)
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17. Internet
 Is one of the network applications.
 A global communication system where computer
networks are interconnected which uses TCP/IP
(Transmission Control Protocol/Internet
Protocol).
 Is a hardware and software infrastructure that
provides connectivity between computers.
 Carries large set of information that is shared
and used by millions of people worldwide.
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18. Working on Internet
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19. Email - I
 Stands for electronic mail, which is a method of
communication.
 Is just like a letter. Unlike letter, email exchanges
messages from one computer to another computer
over an electronic network like internet or Internet
service provider.
 Email address structure
 For example design@jetkinginfotrain.com, where
design is the user name and jetkinginfotrain.com is the
domain name. The sign @ is there in every email
address to separate the username and domain name.
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20. Email - II
 An email message consists of two components:
 Message header – The message header
contains control information like the email
address of the person who sends mail, recipient
email address, subject of the mail message, time
and date of the message and message size.
 Message body – The message body contains
the content of message.
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21. Question for GD Time Limit – 3 Mins
 What is the difference between Internet and
E-mail?
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22. Working with email
 Perform activity mentioned in Lab no.1 at the
end of this chapter.
 To create an e-mail account in Gmail.
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23. Practical - II
 Perform activity mentioned in Lab no.2 at the
end of this chapter.
 To send an e-mail message.
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24. Practical - III
 Perform activity mentioned in Lab no.3 at the
end of this chapter.
 To read an e-mail message.
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Summary - I
 Computer Network consists of group (or number of
individual computers) of computer and devices which are
connected with each other.
 Computer Networks can be used for many purposes:
 Sharing Files and folders, data and information.
 Sharing hardware resources such as network printer.
 Sharing software as many users connected to network run
the same application program.
 Network can be divided into two main types:
 Client-Server Model
 Peer-to-Peer Model
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Summary – II
 Client/Server is a configuration of the computer network
that includes a server and one or more clients.
 Peer-to-peer is a communications model in which each
party has the same capabilities and either party can
initiate a communication session.
 Computer networks are divided into LAN, MAN and
WAN depending on the geographical coverage area.
 LAN is a small network and easy to create.
 WAN covers a wide geographical area which includes
multiple computers or LANs.
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Summary - III
 Networks are widely used in different fields like financial
institutions, communication services and Internet services
like E-mails.
 Internet is a global communication system where
computer networks are interconnected which uses TCP/IP
(Transmission Control Protocol/Internet Protocol).
 Electronic mail is a computer based method of
sending/receiving messages form one computer user to
another.
 To exchange information through email, you need an
email client and an email server to which the client is
connected.
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28. Mind Map
 Draw a mind map to summarize the session
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