Half Duplex Communication Explained | Generated by AI

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Question: What is the term for a communication method where both parties can transmit information, but not simultaneously?

Answer: This type of communication is known as Half-Duplex (or Two-Way Alternate) communication.


📡 The Three Modes of Communication

To better understand where Half-Duplex fits, it helps to compare it with the other two primary modes:

Mode Directionality Real-World Analogy
Simplex One-way only. One party is always the sender, the other is always the receiver. A radio broadcast or a TV station.
Half-Duplex Two-way, but not at the same time. Information can flow in both directions, but only one way at a time. A Walkie-Talkie. You must wait for the other person to stop talking before you can speak.
Full-Duplex Two-way simultaneously. Both parties can send and receive at the exact same time. A Telephone call or a modern smartphone.

🛠️ Technical Context

In networking, Half-Duplex was very common in early Ethernet setups that used a Hub. Since everyone shared the same wire, if two computers tried to “talk” at once, a collision would occur, and the data would be corrupted.

Modern networks (using Switches and Fiber Optics) almost exclusively use Full-Duplex, which allows for much higher speeds and zero collisions.

Key Rule: In Half-Duplex, the entire bandwidth of the channel is used by whichever party is currently sending.


Would you like me to explain how Ethernet uses CSMA/CD to manage these “turns” in a Half-Duplex environment?


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