what is internet and computer network:

what is internet

internet is a connects billion of computer across the word with each other.

what is computer network :

a computer network is a group of computers that are connected with each other in order to share information and resources.

internet and computer network

type of computer network :

there are many type of computer networks but they are broadly classified in three categories.
  1. Local Area Network (LAN)
  2. Metropolitan Area Network (MAN)
  3. Wide Area Network (WAN)

1) Local Area Network (LAN) :

computer network which is dedicated to share information and resources among several personal computers is known as Local Area Network. Lan is computer network covering a small area.

2) Metropolitan Area Network (MAN) :

computer network that usually spread across a campus or a city is known as Metropolitan Area Network (MAN). MAN is connecting a campus or city mostly uses wireless communications or fiber optical connection.

3) Wide Area Network (WAN) :

Wide Area Network (WAN) is covers a wide geographic area like state or country. communication in a WAN is done by telephone lines, satellite dishes and radio waves to span a large geographic area.

Network topology :

network topology is a pattern in which computers in a Lan are connected to each other.
five type of network topology are used in network topology, which are as follows
  1. Bus topology
  2. Star topology
  3. Ring topology
  4. Hierarchical topology
  5. Hybrid topology

#1 Bus topology :

A bus topology is a network architecture in which a set of computers are connected via a shared communications line, which is know as bus
bus topology

advantage of bus topology :

* bus topologies are the cheapest topology.
* which is easy to implement and extend for quick setup of computer network.
if one computer system fails then it will not effect the function of other computer networks.

disadvantage of bus topology :

*limited number of computers can be connected using bus topology.
*it provided low security.

#2 Star topology :

A star topology consists of one central computer which acts as a router to transmit massages to other computer in the network. thus, all computer may communicate with each other by transmitting to, and receiving from, the central computer only.
Star topology

advantage of Star topology :

* if any transmission line connecting any computer to the central computer fails, it will result in the isolation of that computer from all others computers in the networks.
* it is reliable and secure topology for computer network.

disadvantage of star topology :

* any failure of the central computer can disable the entire network,
* administration of computer network which have star topology is costly in the long term.

#3 Ring topology

in ring topology, each computer in the networks is connected to two other computers. thus, it is crating a ring type structure.
Ring topology

advantage of Ring topology :

* a computer network having start topology.
* All computers have equal access control.
* high-speed data transmission

disadvantage of Ring topology :

* if any computer fails, the rest of the networks also fails.

#4 hierarchical topology / tree topology

a collection of star networks arranged in a hierarchy is known as hierarchical topology. in hierarchical topology unlike the star topology, the function of the central computer may be distributed.
hierarchical topology

#5 Hybrid Topology

hybrid topology use a combination of any two or more topologies in such a way that the resulting topology does not have one of the standard forms.
A hybrid topology is always produced when two different basic network topologies are connected like star ring topology and star bus topology.