Network: - A group of computers
that are connected to each other for the purpose of sharing computer software
& hardware resources between many users.
Or
Joining
two or more computers each other is called network.
Like:
- CD drive, hard disk drive and sharing information is called network.
Networking: - Sharing data
over the network is called networking.
Need for
networking: - Now
a day, It plays the most important role in our modern life because without networking
we cannot connect one people to another people and one organization to another
organization quickly.
Communication technology has entered into the face
because all the media are interconnected. Some of popular modes of
communication are: -
Ø Talking
Ø Letter
Ø Telegrams
Ø Telephone
Ø Fax
machine……………..etc.
Data
communication networks: - It has become possible mainly because of computer.
This technology involves transfer information in the form of object. Like: -
text, picture, sound…etc. computer is the device that allows user to send and
receive this object. Computer networking is the best sources for data
communication as local & global.
When the computer is inter-connected the user of
these machines can share data stored in computer. Data is either in primary
& secondary.
Type
of networking: - Networking
has been developed on several labels from local & international in diverted
sector of society.
Networks used by
government organization for referred travel information from database, at banks
sector, merchant etc.
There
are many types of computer networking as given below: -
Ø LAN (Local Area
Network)
Ø WAN (Wide Area
Network)
Ø MAN
(Metropolitan Area Network)
LAN (Local Area
Network): - A
system of network computer and other hardware like: - printer that are
relatively close proximately to one other. LAN networking type used for local
area network like one computer to another computer, room, a single building, a
ship or an aircraft.
Note: -
o
Transfer
data at high speed
o
They
exist in a limited geographic area
o
Their
technology is generally less expensive
WAN (Wide Area
Network): -A
Wide Area Network is a data communication network that work is one state to
another state. It is a geographical communication network and its works in
railway station, banking sector, and big organization…….etc. It connects with router
to use this network.
MAN
(Metropolitan Area Network): -A Metropolitan Area Network is a
basically bigger version of a LAN and normally uses similar technology. It
might cover group of corporate office or cities and might be entered provide or
public. A man can support both data and voice and might even to relate to the
local cable television network.
MAN provides to
the network very high speed and its use manually a metropolitan city. It works
same as CAN (Campus Area Network).
Network Topologies:
-A
network topologies is a geometry arrangement of nodes and cables link in a LAN
and it used in two general configurations i.e. Bus and Star topologies.
This two topologies define how does connected to one
another. A node is an active device connected to the network such as computer
or a printer.
Topologies
are a physical layout of the network which provides another way to differentiate
between networks. Different network topologies offered different advantage in
cost complex sting.
There are three
type of network topology: -
Ø The Bus topology
Ø The Ring
topology
Ø The Star
topology
The Bus
topology: -It
is the simplest of all topologies in the layout the network being at one end
and then connects to each other for ex.
![](https://i.imgur.com/NMle1Ue.jpg)
People
often referred to this as daisy changing to computer together. It is useful and
easy to put together for a small class room or lab network.
The Ring Topologies: -The
next topology used in networks is the ring topologies. It is very similar to
the bus topology accept that the two ends of the networks connect to for a
complete ring foe ex: -
![](https://i.imgur.com/mK6cnlQ.jpg)
The
chief advantage of topologies over bus topologies is that if break occurs in the
ring computer network will still be able to communicate by going to the other
way around the ring.
The Star
Topologies: -In this layout the network designers design one
location as the center of the start. Network architecture consist a central HUB
(electronic device with multiple slots to connect more than one computer). The
Star topologies are often used within a LAN.
![](https://i.imgur.com/TE9kGeC.jpg)
In
a star network several device are connected to a device.
Component of Network: -The
computer network is a system that has several devices for gathering data processing
and distribution.
The components of network are for
LAN: -
Ø The workstation
& the Server
Ø NIC (Network
Interface Card)
Ø HUB
Ø Switch
Ø Cables
Ø RJ-45 Connector
Server:
-A
network storage data can be used by many user. The computers that are
responsible to store all the data and also to update information is called
server.
Its function
stores all files in the system that may either contain program or data. It also
makes those data available for the user. Since its storage data is in the form
of files, it referred to as file server.
The
Workstation: -The
computer that are responsible to accept the user inputs, add transfer the data
to the server for processing are called workstation.
The workstation can access all resources
of the server. These resources include the CPU, Memory, Input/output
device……..etc.
NIC
(Network Interface Card): -It is an electronic card which used to connect wire
(Networking wire with PC and HUB & Server).
HUB: -It is an
electronic device which used to connect with Workstation. It is responsible to
accept transfer data between workstation.
Cables: -A flexible
metal/wire used in a line of communication is called cables.
There are various kinds of cable: -
Ø Twisted Pair
Cable
Ø Co-Axial Cable
Ø Fiber Optics
Cable
Twisted Pair
Cable: -It
is used for telephone. They contain two wire of conducting material include
from each other. They appear twisted hence the name.
It includes the
following layer: -
a)
The
inner layer is a conductor of wire covered by the insulating material. The
conductor is generally made up of copper.
b)
The
middle layer is including layer repairing the inner section from the other
layer.
c)
The
outer layer conductive material that is in the form of mesh surrounding the
insulating tube.
Co-Axial Cable:
-It
is used to transmitting data information from various workstations. The cable
transmits efficiently over a limited geographic area generally a LAN.
Fiber
Optic Cable: -It
is used to carry data and information and transmit then in the form of light
rays. They are free only any outside interface like noise.
It is capable of
transmitting data in huge volume and high speed. The chances of data being
cropped threw the transmitting line are very less.
Software: -software is a
programmed instruction or code where user can access any type of information
that means user can work upon any application software.
There are three type of software: -
Ø System Software
(Operating System)
Ø Application
Software (Ms-Office, Tally, C language….etc)
Ø Utility Software
(Antivirus)
These facility
are provide by a group of software programmed called the network operating
system.
The services
provide by a network operating system are: -
a)
Storage
and retrieval of files
b)
Keeping
information secure
c)
Access
to its resources by multiple user of the system
d)
Identifying
and connecting various workstations with the server.
User: -There are two
type of network user: -
Ø The system
administrator
Ø The End User
The System
Administrator: -The
computer networks are large and complex system made up of the server and
multiple workstations like any other system it required a manager. The person
who keeps a track of the problems in the system and rectifies them is called
the system administrator
Its job include:
-
a)
Creating
user and managing them.
b)
Providing
access of resources to its users.
c)
Protecting
the network from unauthorized access.
d)
Any
other external user of the system should not edit and make changes to the data
and resources of the user or the system.
The End-User: -The End-user is
the people who access the network from the workstation. Each user has own
separate workstation. The different end user can be broadly classified as: -
Ø Data entry
operator
Ø Application user
Ø Programmers
Unit - 2
Advantages
of Networking
As
we know very well Networking is the most useful technology field due to workstation.
Networking system helps to do any type of official task and find out about the
specific topic easily. There are many branches of an organization in different
place and that organization maintain all official requirements i.e. accessing
of data and transaction of product ………….etc. based on networking system.
There are following advantage of networking: -
Ø Exchange
of Data
Ø Access
of Internet
Ø Sharing
& Resources
Ø Creating
Backup
Logging in: -The
process of connecting your computer or workstation to a specific server is
called Logging In.
Logging out: -The
Log out command breaks the connection to the server after logout the computer exit
from the server.