This PPT was prepared as part of a virtual group discussion during our Third Yr Engineering. It touches on some computer networking topics briefly.

1. Network
Models
A Presentation

2. C O N T E N T S
Introduction -- Anjali
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2
3
4
5
6
7
8
9
10
11
12
13
14
15
How The Internet Works? -- Niraj
Computer Networking Models -- Rohit
OSI Model -- Nasir
Physical Layer -- Manish
Data Link Layer -- Yogita
Network Layer -- Trishala
Transport Layer -- Shadab
Session Layer -- Onkar
Presentation Layer -- Ibrahim
Application Layer -- Kunal
TCP/IP Model -- Arbaz
IPv4 Exhaustion & Requirement of IPv6 -- Aftab
The Conclusion -- Monis
Difference Between OSI & TCP/IP Models -- Avinash

3. INTRODUCTION
Internetworking is the practice of inter-connecting
multiple computer networks.
The resulting system of inter-connected networks are
called an inter-network, or simply an internet.
The challenge when connecting various systems is to
support communication between disparate
technologies.
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4.  The Internet is a global system of interconnected computer
networks.
 When two or more electronic devices (e.g.
computers) are connected so that they can communicate, they
become part of a network.
 Web pages are created using the formatting language HTML; so
anyone can be sure that every device will display the web page in the
same way.
HOW THE INTERNET WORKS?
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5. COMPUTER NETWORKING MODELS
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There are generally two networking models
 OSI Model
 TCP/IP Model
TCP/IP Model is mostly used in the
present networking world.
These Models are based on Client-Server
communication theory.

6. OSI stands for Open System
Interconnection
OSI consists of seven layers, and each
layer performs a particular network
function.
OSI model divides the whole task into
seven smaller layers.
OSI model was developed by the
International Organization for
Standardization (ISO) in 1984.
OSI Model
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7.  Physical layer is the lowest layer of the OSI reference model.
 The physical layer defines the transmissioninterface between
devices and transmission medium.
 The sender and receiver are synchronized at bit level.
PHYSICAL LAYER
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8. DATA LINK LAYER
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 Data Link Layer is the second layer of OSI
Layered Model.
 This layer is one of the most complicated
layers.
 Responsible for converting data stream to
signals bit by bit and to end that over the
underlying hardware.

9.  It determines the route from the source to the
destination and also manages the (network)
traffic problems.
 The main role of the network layer is to move
the packets from sending host to the receiving
host.
NETWORK LAYER
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10.  The main role of the transport layer is
to provide the logical communication
between application processes running
on different hosts.
 The transport layer is represented by two protocols: TCP and UDP.
 TCP i.e., Transmission Control Protocol provides full transport layer services
to applications.
 UDP i.e., User Datagram Protocol is used when reliability and security are
less important than speed and size.
TRANSPORT LAYER
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11. SESSION LAYER
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 It establishes, manages, and terminates
the connections between computers.
 It adds synchronization points or
checkpoints in data streams for long
communications.
 This ensures that data streams up to the
checkpoints are successfully received and
acknowledged.

12.  The Presentation Layer is also called as Translation Layer.
 Responsible for the formatting and delivery of information to the
application layer.
 Functions :
 Encryption/Decryption; data encryption translates the data
into another form or code.
 Compression; reduces the number of bits that need to be
transmitted on the network.
PRESENTATION LAYER
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13.  Application Layer is at the top level of
the OSI model.
 Manipulation of data is done in this
layer by using more than 15 protocols.
 A widely-used application protocol is
HTTP (HyperText Transfer Protocol),
which is the basis for the World Wide
Web(WWW).
APPLICATION LAYER
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14.  Developed byDepartment of
Defence's Project Research
Agency( DARPA) to connect remote
machines.
 The overall idea was to allow one
application on one computer to talk
to(send data packets) another
application running on different
computer.
TCP/IP MODEL
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TCP/IP stands for Transmission
Control Protocol and Internet
Protocol.

15. DIFFERENCE BETWEEN OSI &
TCP/IP MODELS
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16. IPv4 EXHAUSTION & NEED OF IPv6
IPv4 addresses are running out.
The solution is IPv6.
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17.  Internetworking is the internet; a network of
networks based on many underlying technologies.
 There are several layers involved in making
internet work as we see it.
 Various kinds of tools, from wires to towers to
display screens, work together to form a net of
communication.
CONCLUSION
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18. 2.8Million
Social Media
posts 2.5 Million
Website
search queries 27.2Thousand
Review
posts
100
Hours
of Online
videos
201Million
emails
sent
57 Thousand
Pictures
posts 50.7Thousand
Thoughts
posts
EVERY
MINUTE