Computer network

1. Computer Network is a
network in which multiple
computers are connected
to
other to share
information and
resources.
In today’s era , people in one
part of the world can
communicate with those in
the other corner of the world. All this is possible because of the
technological advancements in communication systems.

2.  Easy data sharing
Easy access to data
Cost effectiveness
Fault tolerance
Quality of service
Security
No need to keep hard
copies of documents

3. A router is a communication device
that is used to connect two logically
and physically different networks.
Router uses the IP address.
Network Interface Unit (NIC or NIU) is
a device that allows communication
of computer system over the
network.
Hub is a hardware device that connects
multiple computers or other networks
or other network devices together.

4. Switches are small hubs that
send data directly to the
destination rather than every
part within network. A switch
is smarter device than hub.
A repeater is a device that
boosts the signal being
transmitted on the network.
The full form of MODEM is
Modulator Demodulator. It is a
hardware device that allows a
computer to send and receive
information over telephone lines.

5. Communication channel is a medium through which data is
transmitted from one location to another.
Wired or guided media
Wireless or unguided media

6. It covers a small physical area
like a home, office or small
group of buildings, such as a
school or airport.

7. MAN consists of a computer network
across an entire city, college campus
or small region. A MAN is larger than
a LAN.
WAN is a computer network that
covers a large geographic area. The
Internet is the best example of a
WAN.

8. PAN is a computer network
organized by an individual
person within a single
building. PAN are used for
communication among
various devices, such as
telephones, personal digital
assistants, fax machines and
printers that are located
close to a single user.

9. Network security is ensured in
many ways. Two of the most
common ways are as follows:
Each authorized user is given
a unique username and password
for accessing the network.
Different users are given
different types of access rights,
such as read only access, read-
write access, and no access.