A MAN ( Metropolitan Area
Network) is used to connect computers to cover the city or town. The range may
be approximately 50 Kilometers. Normally
cables and fiber optic cables are used to connect computers. The routing
of the messages are fast. Normally central
library in a city may be connected by a MAN, so users can access the information.
Figure 5.2 shows a typical view of Metropolitan Area Network.
Figure 5.2
Metropolitan Area Network
Wide Area Network (WAN)earn money online
A
WAN (Wide Area Network) covers large distance like state, country or
continents. The WAN uses the fiber optics, cables and even satellites also.
Here communication circuits are connected with the help of hardware device
called routers. Routers forward small pieces of information called packets from
one to another. Internet is the popular
one comes under WAN. Some of the
examples makes use of internet are reservation of airplane tickets, railway
tickets and even cinema tickets. Another facility called e-commerce, where business is carried out
through internet. Here people can buy books, articles and so on through registering
their wants through the internet. Figure 5.3 shows a typical view of Wide Area
Network.
Fig 5.3 Wide Area
Network
5.3 Internet
The
internet is a massive wide area network
,connecting thousands of computer networks around the world. The internet
is a world wide “network of networks”. It is a collection of thousands of
smaller networks in different countries around the world. It links thousands of
academic government, military and public computers, enabling millions of people
to share information and other resources.
Internet
pathways are used to exchange digitized computer data. The basic services that
form the foundation of the internet are e-mail , telnet and FTP. With internet
we can easily exchange electronic mail with friends and family anywhere in the
world.
Telnet
allows you to connect to a remote computer. We can access any of the public
services or tools and library databases at the remote site. FTP(File Transfer
Protocol) provides for transferring files from one computer to another across
the internet.
Internet
has many uses. For individuals, the most important uses of internet are e-mail
and surfing the Web. One can read the topics of interest like sports, a hobby,
a country or any place of interest.
The e-mail
stands for electronic mail. One of the major features of computer networking is
that messages can be sent electronically to various terminals on the network.
The messages are sent very quickly and accurately. E-mail uses the concept of
Storing and forwarding messages. It saves a lot of money for the users. Here
user registers his/her account with one of the providers. The e-mail account
normally contains username and the provider name. For example abc @ yahoo.com ,
represents abc is the name of the user , who is registered in yahoo
provider.
1.4 Summary:
- Computer
network is defined as a interconnection of autonomous computers.
- Computer
networking enables us to connect
computers to share data, application software and hardware devices.
- Networks
allow sharing of information among various computers and permit users to
share files.
- A LAN
or local area network connects computers and peripherals in a limited
area.
- A MAN
covers the city or town.
- A Wide
Area Network covers a large area.
- The
internet is a massive wide area network, connecting thousands of computer
networks around the world.
- E-mail
is a cost effective communication
5.5 Quiz questions
- Computer
network defined as a interconnection of
---------- computers
2. Computer
network allows user to ----- the
resources
3. --------
network confined to hall or building.
4. ------- is
one example of WAN.
5. ------
business is carried our through internet.
6. Small piece
of information called ---- are forwarded by router in Internet.
