Data Transmission in Computer Networks
In this tutorial, we are going to see What is data transmission in computer networks?
The purpose of a network is to send information from one computer to another. To do this, we must first determine the type of coding of the data to be sent, meaning its computer representation. This one will be different according to the type of data, because it can be :
- Sound data
- Textual data
- Graphic data
- Video data
- …
The representation of these data can be classified into two categories:
- Digital representation: this means that the information is coded into a set of binary values, which is a sequence of 0 and 1
- Analogical representation: this means that the data will be represented by the variation of a continuous physical quantity
Data transmission medium:
In order for data transmission to take place, there must be a transmission line, also called a transmission channel, between the two machines.
These transmission channels are made up of several sections allowing the data to circulate as electromagnetic, electrical, light, or even acoustic waves. We have then a vibratory phenomenon that propagates on the physical support.
Coding of transmission signals:
In order to have an exchange of data, a choice must be made for the coding of the transmission signals, which depends essentially on the physical medium used to transfer the data, as well as the guarantee of the integrity of the data and the speed of transmission.
Simultaneous data transmission:
Data transmission is “simple” when only two machines are communicating, or when only one piece of data is being sent. Otherwise, it is necessary to set up several transmission lines or to share the line between the different actors of the communication. This sharing is called multiplexing.
Communication protocols:
A protocol is a common language used by all communication actors to exchange data. However its role does not stop there. A protocol also allows :
- The initiation of the communication
- The exchange of data
- Error control
- A “friendly” end to the communication