what is network topology and its types

What is Network Topology 

A Network Topology is the arrangement in which computer system of network devices are connected to each other ,Topology may define both physical and logical aspect of the network both Logical and physical topologies could be same or different in a same network .

How many type of Topology 

1- Bus Topology - Bus topology is a network  in which every computer and network devices is connected to single cable . It transmits the data from one end to another in single direction. No bi-directional feature is in Bus topology.

Bus Topology

Advantages...

 it is good for small network.

The cost of topology is less then other topologies.

Disadvantage...

in these topology if any network connection is cut or off then the connection of other computer automatically off .

if the traffic was high then network working very slow.

2- Star Topology- In star topology, all the devices are connected to a single hub through  a cable .this cable hub is the center node and all other nodes are connected to the central node. the hub can be be passive in nature not intelligence hub such as broadcasting devices at the same time the hub can be intelligence known as active hubs active hubs have repeaters in them.

Star Topology 

Advantages...

Each device require only one port to connect to the hub.

its good  for medium network.

Disadvantage...

Cost of this topology is very high.

Performance is based on the single concentrator hub.

3- Ring Topology - In ring topology each host machine connects to exactly two other machines creating a circular network structure when one host tries to communicate or send message to a host which is not adjacent to it the data travel through all intermediate hosts. Failure of any host results in failure of the whole ring. Thus every connection in the ring is a point of failure.

Ring Topology 

Advantages...

 The possibility of collision is minimum in this type of topolpgy.

cheap to install and expand.

Disadvantage...

Installation and configuration is difficult.

Cost of maintenance is very high.

4- Mesh Topology - In these type of topology , a host is connected to one or multiple hosts. This topology has hosts in point to point connection with every other host or may also have hosts which are in point to point connection to few hosts only . hosts in Mesh topology also work as relay for other hosts which do not have direct point to point link.

Mesh Topology

Advantages..

it is robust .

Provides security and privacy.

Disadvantages..

installation and configuration is difficult.

Cost of maintenance is very high.