The document discusses three types of transmission modes between linked devices: simplex, half-duplex, and full-duplex. Simplex mode allows communication in only one direction, half-duplex allows communication in both directions but not simultaneously, and full-duplex allows simultaneous communication in both directions. Each mode is compared to traffic flow examples like a one-way street, one-lane road, and two-way street.

1. Transmission Mode

2. Transmission Mode
The term transmission mode is used to define the direction of signal flow
between two linked devices. There are three types of transmission modes:
1- simplex
2- half-duplex
3- full-duplex
Simplex
In simplex mode the communication is unidirectional as a one-way street.
Only one of the two stations on a link can transmit the other can only
receive.
For Example – Traditional monitors and keyboards use the Simplex
transmission mode. In this case, the monitor can only generate the output,
and the keyboard can only introduce an input in the system.

3. Half Duplex
In half duplex mode, each station can both transmit and receive but not at
the same time. When one device is sending the other can only receive.
The half duplex mode is like a one –lane road with two directional traffic.
While cars are traveling one direction cars going the other way must wait.
For Example – A walkie-talkie uses the Half-Duplex Transmission Mode. Here,
we send messages in both directions, but the transmission till occurs in one
direction at a time.

4. Full Duplex
In full-duplex mode (also called duplex), both stations can transmit and
receive simultaneously. The full-duplex mode is like a two way street with
traffic flowing in both directions at the same time.
For Example – Telephone networks that establish communication between
two people via a telephone line use the Full Duplex method. Here, the
individuals can listen as well as talk at the very same time.

5. Difference Between Simplex, Half Duplex, and Full
Duplex Transmission Modes