Transmission mode defines the direction of the flow of data between two communication devices connected over a network. Simplex, Half Duplex, and Full Duplex are major types of data transmission modes. It is also known as data communication mode or directional mode.
What is Data Transmission Mode?
The data transmission mode is a method of specifying the direction of data flow between two devices connected over a network for data and information sharing. A data transmission mode identifies the direction of data flow from one device to another in a network.
Types of Data Transmission Modes in Computer Networks
The physical layer of the Open System Interconnection(OSI) Layer Model decides how the data is transmitted in a network. Its main function is to specify the direction of data flow through which the data travel to reach the receiver or node. Three main types of data transmission modes are:
- Simplex Mode
- Half-Duplex Mode
- Full-Duplex Mode
Simplex is the data transmission mode in which the data transmission is unidirectional, only in one direction. When two devices are linked in simplex mode only the sender device can send data while the receiver only receives data. It cannot be transmitted in both directions.
In simplex mode, data moves only in one direction similar to a one-way street. The direction of flow never changes. In simplex mode, a device just only sends or receives data. It cannot be able to perform both actions. Examples of Simplex modes are Radio and TV transmission, keyboard, etc.
Advantages and Disadvantages of Simplex Mode
|Enquire full capacity of the channel during data transmission||Don’t support two-way communication|
|Low chances of data traffic issues||No mechanism to transmit information back to the sender|
The half-duplex mode enables the flow of data in both directions but not at the same time. Data can flow in one direction at one time. In other words, each device in a link can transmit and receive the data but not at the same time.
The speed of the half-duplex mode is slow. An example of half-duplex communication is internet surfing where there is no need for communication in both directions at the same time. The user enters a command in order to request for a web page. The web page is downloaded and displayed before the user.
Advantages and Disadvantages of Half-Duplex Mode
|It optimizes the full capacity of the transmission channel||May occur delay in transmission due to one-way communication at a time.|
|Enables two-way communication||Two-way communication but not at the same time|
Full-Duplex is the data communication mode in which the data can travel in both directions simultaneously. The full-duplex mode is a faster way of data transmission as it is bi-directional in nature. Time is not wasted in changing the direction of data flow.
The bandwidth of full-duplex mode is double as compared to the half-duplex. In this communication mode, the capacity of channels is divided between two directions. An example of full-duplex mode is a Telephone Network, in which both persons can talk and listen to each other at the same time.
Advantages and Disadvantages of Full-Duplex Mode
|Two-way communication at the same time||No dedicated path exists because the communication channel divided into two parts|
|Faster than Half-Duplex mode||Improper utilization of channel bandwidth as there exist two sperate paths|