Data can flow in different ways of data communication or transmission modes in networking. Those can be defined as one device to another or two devices can communicate in Simplex, Half-Duplex, or Full-Duplex.
Simplex Data Flow
The Simplex mode of communication is unidirectional, it is a one-way data flow and communication medium. Simplex mode can use the entire capacity of the channel to send data in one direction.
Half-Duplex Data Flow
A half-duplex mode allows each station to transmit and receive at the same time, but not simultaneously. Half-duplex data communication allows it to receive and transmit data simultaneously, but not simultaneously.
There is no need for communication in both directions at the same time in this mode. In both directions, the entire capacity of the channel can be utilized.
Full-Duplex Data Flow
The full-duplex mode of data communication allows both stations to transmit and receive simultaneously. Through two-way communication, it can send and receive data.
One of the common examples of full-duplex communication is the telephone network. When two people are communicating by a telephone line, both can talk and listen at the same time.
When continuous communication is required in both directions, the full-duplex mode is used. There must, however, be a division of the channel capacity between the two directions.