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What is Data Communication – All about Data Communication System – Digital Namanji

Data Communication is mainly a interchange of data between two or more devices. Know in Details What are the Basic constituents of Data Communication, and its Direction of the data flow. Also Check What is Wired & Wireless Data Communication Transmission Media available. Check this Article to check every detail about Network topologies, signal, and transmission of Data Communication. Data Communication also includes Analog and digital signal which we must know in details. So, check this article till the last and get every detail related to it.


Data Communication

It is termed as an interchange of data between two or more two devices (computer) with the help of wire cable, wireless, vacuum, or with the help of radiation. 

It is necessary for any communication of data that we use the devices in any communication to be the part of the communication system. 

Otherwise our data transfer may get leaked, misused or not worked.

Communication systems are composed of software and hardware devices and programs.

Data communication comprises two things: the sender and the receiver.

Senders are the devices who transmit the data and receivers are the devices who receive the data. 

Local data communication comes under the same area or within the same building in which transmission of data occurs within the same building.

Telecommunication is a term which comprises television, telegraphy and telephony. It talks about communication at distance.

Computers used binary information for conveying data transfer. 

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Basic of the communication

Five important constituents of data communication are as follows. 

  • Message 
  • Sender
  • Receiver
  • Medium
  • Encoder & Decoder

Message – message is the data that is in the form of text, sound, video images and number.

Sender –  With the help of the sender we transfer the data from one place to another place. With the use of a sender that is a device like computers, telephone, workstation, and video camera, etc data can be transferred.

Receiver – Receiver is a device through which transmitted data or messages can be received. A receiver can be a computer, workstation, fax machine or a printer.

Medium – It is the way through which data or messages are sent from sender to receiver. It is also known as a communication channel. For local area communication channel can be a wire cable and for long-distance communication in which sender and receiver are located in different locations communication channel can be a satellite, fiber optics, telephone lines or microwave, etc.

Encoder – Computers use digital signals for their work and communication channels usually work on analog signals. As we know computers use digital signals and So for transferring data from sender to receiver we need to convert (encoded) digital signals into analog or in the signal that communication channels or transmitted mediums used to transmit the data. This process is called Encoding and the device that way out this function is called an encoder.

Decoder –   After encoding, we need to convert the signal of carrier media into digital media because the receiver can be a computer and it uses a digital signal so there is a need to convert (decoded) encoded signal back into a digital signal. This process is called Decoding and the device that uses this function is called Decoder.


Direction of the data flow 

  • Simplex 
  • Half-duplex
  • Full-duplex

Simplex – It is defined as the flow of data only in one direction or the unidirectional flow of data takes place. In the simplex mode of data flow, there is only one device of the two devices that can transmit the data to another device, another device only can receive the data.

For example-

In a computer system, there are two devices: a keyboard and a monitor. We use a keyboard for transferring the data and the monitor is the receiver here.

There is a unidirectional flow of data taking place.

Half- duplex –  In half duplex data flow takes place in both directions but at different times. In this method both devices can be sender  and receiver but at different times. That means until data is not sent from one device to another and it is received by the receiver , the receiver or another device can’t send data back to the sender or the device who sends data to it.

Full-duplex –  In full-duplex, both devices can send data to another one at the same time. For example, two people are talking on their phones. They can say their thoughts and listen also at the same time to each other and can reply also. full-duplex mode is required when communication is needed from both sides at the same time. 

Network topologies, signal, and transmission

Network topologies are as following types ..

  • Point to point
  • Bus 
  • Star
  • Ring 
  • Mesh 
  • Hybrid

Point to point – In this mode, two ends are connected together directly through a link. The communication channel between these two ends is used only for these two systems only. Point to point connection uses an undeniable length of the wire to connect the two ends.

Bus – In bus topology all devices are connected with the same cable or wire. In bus topology there may be loads of data when all devices send data at the same time.

Star – In star topology point to point connection is used. There are many devices connected with a central device which is also known as a hub with point to point connection.

Ring – In a ring topology, many computers are connected in a circular or ring manner. In this mode of topology one computer is connected with two adjacent computers and forms a circular-like structure. 

 Mesh – In mesh topology there is a mesh like structure that is formed in the networking of the computer. There are many devices used and a single device is connected to more than two devices. It means there are many I/O ports used in a single device to connect more devices along with it.

Hybrid – Two or more than two types of topologies are used to form hybrid topology. 

For example … 

Ring topology is connected with star topology to form hybrid topology.


Transmission Media 

Transmission is the process through which signals are transferred from one location to another. And signals can be digital or analog. For transmission of signals wired, wireless electromagnetic wave signals, optical fibers, or radiation can be used.

Wired Transmission Media – It is also known as the Guided Media or Bounded Media. It uses a narrow path by using physical links for transmission. The feature of transmission media is it provides high-speed and secure transmission.

Wireless Transmission Media – It is also known as the Unguided media or Unbound media. It does not use any physical medium for transmission. It is less secure and used for a large distance.

Analog and digital signal 

Analog signals are defined as a continuous wave of signals having a continuous range of values. These naturally occur in nature for example human voice, natural sound. 

Digital signals are those having discontinuous signals with discontinuous values. These are used in binary waveforms and the devices that come under digital signals are computers, optical drives, and other electronic devices.

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In this post we share complete information about Data Communication, we try to cover all the topics in case any thing is missing or you want to know more then share in comment section. if you like this article the share.

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Digital Namanji
Digital Namanji
Hello friends, I am Naman, Technical Author & Founder of Digitalnamanji. I enjoy learning things related to new technology and teaching others. I request you that you keep supporting us in this way and we will continue to provide new information for you.


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