Introduction to Internet. Part 1 Of 4. Class X.

1. INTRODUCTION
TO INTERNET.

2. 1.0 INTRODUCTION
• The development of micro computers and merging of computers and
communications has profound influence on the way computer systems are
organized. The old model of isolated computers serving the needs of
organizations has been replaced by large number of separate but inter
connected computers known as computer networks. The connection
between two computers can be copper wire, fiber optic cable , microwaves
or communication satellite. The use of computer networks was the result
of US Defence Project ARPANET (Advanced Research Project Agency
NETwork) initiated around 30 years back to develop computer network
connecting a few computers of universities and research organizations in
USA for data transfer between computers.

3. • The computer networks have many uses, One of the primary use is
making available all programs, data and equipment to any one on
the network irrespective of physical location of the users. In other
words a user who is 1000 km away can access data on remote
computer as though it was local. Thus we can say that Internet is a
network of tens of thousands of computer networks. Every network
and every computer on these networks exchange information
according to certain rules called Protocols. Two computers working
with different operating system can communicate because of the
same Protocol. Two protocols used for working with the Internet are
Internet Protocols or IP and Transmission Control Protocol or TCP.

4. • We can often see these mentioned together as TCP/IP
when references are made to the software needed to
make an Internet connection. Each network and
computer system on the Internet has an Internet
address called an IP address. The address is used to
exchange information, and, or receive e-mail, etc

5. 1.1 USES OF NETWORK
• Computer networks provide high reliability by making available alternate sources
for supply. For example, the programs and data can be replicated on two or more
machines so that if any one of the machines is not available, the other copies can
be utilized. Similarly the presence of multiple computers on the network enables
even if one of the systems breaks down, the other can be able to take over the
work failed ones.
• Another use of computer networks is saving money. Small computers have much
better performance compared to their price. The larger computers (Main frames)
may be 10 times faster than smaller ones but the cost is 1000 times more than
smaller computers.

6. • This imbalance made many system builders to go for a ne for a network of smaller
components. We can add more and more ne computers to the network whenever
work load increases. Hence computer network is easily expendable.
• Very important usage of computer network is communicate media. With the network, it is
easy for two or more people who live far apart work together. The collection of
interconnected networks is called inter-network or internet. The specific inter-network,
which uses TCP/IP is the INTRANET not the INTERNET.

7. 1.3 WHO GOVERNS THE INTERNET ?
• There are no single organisation who owns the Internet, there are number of volunteer
organisations which are responsible for different types of activities such as :
• IAB - THE INTERNET ARCHITECTURE BOARD, which is responsible for
approving standards and allocating resources.
• IETF - THE INTERNET ENGINEERING TASK FORCE , which is responsible for
discussing and investigating the technical problems on the Internet.
• InterNIC - This organization is responsible for providing registration services to
Internet users.

8. 1.4 REQUIREMENTS
 Internet Connection
 Modem
 Telephone Line
 Program which control the communication of data
over the hardware component.

9.  ISP (INTERNET SERVICE PROVIDER)
• An Internet service provider (ISP) is an organization that provides
services for accessing, using, the Internet. Internet service providers
may be organized in various forms, such as commercial, community-
owned, non-profit, or otherwise privately owned.
• Internet services typically provided by ISPs include Internet access,
Internet transit, domain name registration, web hosting, Usenet
service, and colocation.

10.  MODEM
• A modem is a computer peripheral that allows you to connect and communicate with other
computers via telephone line, it stands for MOdulator – DEModulator .
• Modem come in different speeds and is measured in bps or bits per second. 28.8 Kbps
modem transmits data up to 28,000 bits per second. A 56 Kbps modem is twice as fast,
sending and receiving data up to 56,000 bits per second. Almost all modem today are 56
Kbps.
• Integrated Services Digital Network (ISDN) is a line by which data is transmitted over
digital telephones lines. ISDN is two to four times faster than modems. Use of ISDN lines
on Internet’s World Wide Web helps transmit or receive text , graphics, sound and videos.
Many ISP’s provide these ISDN lines.

11.  There are two types of modems :
 Internal Modem: An internal modem slips into an expansion slot
provided in the computer. The phone cord is plugged into a jack,
through the back of the computer. It is less expensive than external
modem.
 External Modem: An external modem is placed outside the computer. This
modem is connected to the computer through USB cable or through serial cable
and the telephone is connected to the modem, thus providing computer access
to the outside world.

12. THE END