2. Recap
In the previous class, you have learnt about
• An internet
• History of Internetworking
• Internetworking challenges
• Open System Interconnection Reference Model
• Inter network Addressing
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3. Objectives
On completion of this period, you would be able to know
about
• What is an Internet ?
• History of Internet
• Advantages of Internet
• Internet today
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4. The Internet
• Internet sometimes called simply “the net” is not at all a
network
• It is a vast collection of different networks that uses certain
common protocols
• It provides common services to networks
• It is not planned by any one and is not controlled by any one
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5. The Internet contd…..
• An “internet” (lower case letter i ) is two or more
networks that can communicate with each other
• The most notable internet is called “ Internet” (upper
case letter I) a collaboration of more than hundreds of
thousands of interconnected networks
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6. The Internet contd…..
“The Internet is a structured and organized communication
system that has brought a wealth of information to our
fingertips and organized it for our use”
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7. backbone
Regional ISP
POP
Server farm
NAP
Telephone
system
Router
Corporate
LAN Fig.1 Overview of Internet
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8. History of Internet
• In 1960’s main frame computers are stand alone
machines
• The Advanced Research Project Agency (ARPA) in
the department of defense was interested in finding
a way to connect computers
• In 1967, at the Association of computing machinery
(ACM) meeting ARPA presented its idea for
ARPANET, a small network of connected computers
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9. History of Internet contd….
• Each host computer would be attached to a specialized
computer called an interface message processor (IMP)
• Each IMP had to be able to communicate with each
other IMP’s as well as with its own attached host
• By 1969, ARPANET was a reality and four Universities
were connected via the IMP’s to form a network
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10. History of Internet contd….
• In 1973 Vict.cerf and Bob khan presented a paper
on transmission control protocols (TCP) to achieve end to
end delivery of packets and on the concepts such as
encapsulation ,datagram, and functions of gateways
• Later TCP are split in to transmission control protocols
and internet protocols
• Internetworking protocols became known as TCP/IP
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11. Advantages of Internet
• The Internet has revolutionized many aspects of our
daily lives
• It has affected the ways we do business and the ways
we spend our leisure time
• Perhaps you have sent e-mail to a business associate
• Paid a utility bill
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12. Advantages of Internet contd….
• Read a news paper from a distant city
• Looked up a local movie schedule
• May be researched a medical topic
• Booked a hotel reservation etc…
all by using Internet
“Internet has brought a wealth of information to our
fingertips and organized it fir our use”
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13. The Internet Today
• The internet today is made up of many wide and local area
networks joined by connecting devices and switching
stations
• It is continually adding new addresses and networks and
networks of defunct companies are being removed
• Today most end users who want Internet connection use
the services of Internet Service Provider (ISP)
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14. The Internet Today contd….
• There are International service providers, national
service providers, Regional service providers and local
service providers
• The Internet is run by private companies not by the
government
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15. Fig. 2 Hierarchical Organization of the Internet
ISP9 ISP ISP ISP
X X X X
Regional ISP ……. Regional ISP
Structure
X X of a
national
National ISP ISP
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16. National ISP
National ISP x National ISP
NAP x
x
National ISP National ISP
Interconnection of national ISPs
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17. Summary
In this class, you have learnt about
• Internet
• History of Internet
• Advantages of Internet
• The Internet today
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19. Quiz
2. The protocols for Internet were designed by
a) Vict.cerf and Bob khan
b) Albert Einstein
c) Neapier
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20. Quiz
3. TCP is responsible for
a). Datagram routing
b). Segmentation
c). Error detection
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21. Quiz
4. Internet is run by
a) Government
b) Private companies
c) Both a and b
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22. Questions
1.What is Internet ?
2.List the uses an Internet
3.Write brief history of Internet
4.Explain the hierarchical organization of Internet
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23. Assignment
1. Write the history of Internet
2. Explain different application of Internet
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