The internet

Hey folks!
Good to be back after a long time.

The topic I want to tell you about today is "internet".
well let me clear this first. The word "internet" has been created from - "interconnection of networks".

Any interconnection of networks is termed as an internet.
There is a slight difference between "internet" and THE "Internet" ( notice the capital I). The Internet is the World Wide Web (WWW) as we know of. This is also a interconnection of networks, but this consists of interconnection of a number of networks spread throughout the world.

The internet I am talking about is any general interconnection of networks.
The internet is logically divided into a number of layers, with the layers arranged in a stack like fashion. The layers are namely -

(from the top to the bottom)
1. Application layer
2. Transport layer.
3. Datalink layer.
4. The host to network layer.

The tasks and roles of each layers are well defined and so is the interface between any two layers are well defined. This make is easier to change or modify any layer without disturbing of effecting any other layer.

The Host to Network layer is the layer that is made up of the electrical signals that pass through the wires and make up the 1s and the 0s.

In the data link layer, the information moves in the form of 'packets' - which are units of data. The have a header as well as a trailer attached to it.

The transport layer is the layer that takes up teh responsibility of setting up a connection and ensuring that the data arrives in order and is dutyfully acknowledged (in case of connection oriented protocols) and is ultimately brought down gracefully.

All the network based programs reside in the application layer.


Will talk more about the layers in details later on. Till then, enjoy !!