Question

A transmission mode that can transmit data in both the directions but transmits in only one direction at a time.

(a) simplex

(b) half duplex

(c) full duplex

(d) semi-duplex

This question was addressed to me during an interview.

This question is from Transmission Modes topic in section Data Communications and Computer Networks of Computer Fundamentals

Answer 1

The correct answer is (b) half duplex.

In half-duplex transmission mode, data can be transmitted in both directions, but not simultaneously. The transmission can occur in one direction at a time, meaning the sender and receiver take turns sending and receiving data. This is typically seen in walkie-talkies or CB radios, where one party speaks and the other listens, but they cannot do both at the same time.

Here’s a brief overview of the other modes for comparison:

• (a) Simplex allows data to be transmitted in only one direction (e.g., TV broadcast).
• (c) Full duplex allows data to be transmitted in both directions simultaneously (e.g., telephone conversations).
• (d) Semi-duplex is not a standard term but could be interpreted as another name for half-duplex, although it's not commonly used in technical contexts.

Thus, the transmission mode you're referring to is half duplex, where communication occurs in both directions but only one at a time.