| Computer
Network Tutorial
Networking
Introduction
In this basic network tutorial you will
find basic introduction to data communication
and general overview of the communication
devices, tcp/ip suite, communication cabling,
basic topologies, and wireless communication
technology. Computer networking means
sharing of data and resources between
two or more computers with a medium such
as Ethernet cable, leased lines, router
and even air. Networking is a most widely
used field of the computer technology.
A computer network is comprised of two
or more wired or wireless connected computers.
A simple computer network is made up of
two connected computers. All the computers
in a network can access, share the data
and resources with each other. A computer
network is generally categorized into
the three main types such as LAN (Local
area network), MAN (Metropolitan area
network) and WAN (Wide area network).
A number of the standards are involved
into the certain steps of the data communication
and on these standards certain communication
devices have been developed.
In the computer age, no organization
can work perfectly without a computer
network. The concept and working of the
whole internet is due to the computer
networking. A computer network is a basic
need for any organization to share data
and resources on the small to big level
such as banks, insurance companies, universities,
colleges, multinational companies, corporate
offices and small businesses etc. The
network is made up of different components,
protocols, devices, topologies and mediums
such as cables, routers, leased lines
and air. Following is the basic overview
of each of the basic networking components.
TCP/IP Suite
TCP/IP is a suite of the protocols. Many
protocols are the part of this protocols
suite such as TCP (transmission control
protocol), IP (internet protocol), FTP
(File transfer protocol), HTTP (hyper
text transfer protocol), DNS (Domain name
service), DHCP (Dynamic host configuration
protocols), PPTP (Point to point tunneling
protocol) and many other communication
protocols. The communication on the internet
is carried out by the TCP and IP protocol.
In LAN and WAN networking TCP/IP protocols
play major role in the communication.
An IP protocol ensures the error free
delivery of the data to its destination
by a device known as router.
Additionally, every communication device
on the internet and on the local network
requires a unique identifier, which is
known as a IP address. An IP address is
32 bits, four octets address that is having
a decimal value from 0 to 255. There are
three major classes of the IP address
such as Class A, Class B and Class C.
A typical IP address looks like this form
100.100.1.50 that is four octets that
are separated by the periods.
Topologies
Topology means the physical design and
layout of the network or how the network
devices, computers and components are
arranged. There are some basic topologies
of a computer network such as star, mesh,
ring, bus, hybrid and tree. The most commonly
used topology of a computer network is
a star topology. In the star topology,
all the computers are connected to a central
device known as a hub or switch. Data
in a network passes through the central
devices and then directed towards the
destination computers. The failure of
one computer does not affect the working
of the other computers however, the failure
of the hub or switch results in halting
all the network communication i.e no communication
can occur without the hub or switch.
Network Devices
There are a large number of devices that
are involved in the whole communication
process. These devices include hub, switch,
router, gateway and NIC cards. These communication
devices play an important role in the
overall data communication process. The
communication on the internet is carried
out by a device known as a Router. The
main function of the router is to route
the data (traffic) to its destination.
Router has the IP addresses of the sending
and receiving computers also router has
the capability of finding the best shortest
path to the destination and hence provides
the faster secure delivery of the data.
Different communication devices with different
features are being developed by a large
number of the vendors such Cisco, Intel,
Nortel, DLink, Paradyne, Dell, 3COM, Alcatel,
Fibronics, Triticom, Nextgen, Motorola
and many others.
Cabling
A computer network can be formed wireless
or cabled. In a cabled network, there
are a certain types of the cables required
depending on the type of the network.
The most commonly used cables are the
UTP/STP (unshielded twisted pair/shielded
twisted pair) Ethernet cables also known
as CAT5 cables. In the CAT5 cables, there
are eight cables and four pairs. Each
cable is twisted with its corresponding
cable and thus forms a pair. From these
eight cables, there are two major types
of cables are formed known as straight
over cable and cross over cable. A straight
over cable is used to connect a computer
with a hub or switch and a cross over
cable is used to connect the computers
with each other and to connect the communication
devices with each other such as routers,
switches and hubs.
Types of Networking
There are two basic types of the computer
networking such as peer to peer and client/server
communication. In the peer to peer communication,
there is no central server and all the
computers fall in the same workgroup and
no central domain is exist. Such type
of networking can be seen in the home
or small offices where no computer server
or domain controller is required. In the
client/server networking model, a centralized
server acts as a domain controller and
it controls all the client computers in
the network. All the client computers
depend on the server (domain controller)
for logon access, data, internet access,
printer, scanner, CD-ROM, critical updates
of the distributed applications and all
the other data and shared resources. If
the server gets corrupted or destroyed,
the access of the client machines to the
server stops and communication can exist
from the client to the server or vice
versa.
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