Half duplex

Half duplex, in telecommunications and computer networking, is a communication technology in which information can flow in two directions, but only one direction at any one time. It has limited communication capabilities compared to full duplex technology, in which data can be sent simultaneously in both directions. In a half-duplex system, a single line is shared by both the sender and receiver to either transmit or receive information.

Half-duplex communication has been used in various applications, ranging from simple radio communication to very complex network systems. The most common use for half-duplex is for communication with asynchronous serial devices, such as a modem or printer. It is also used in walkie-talkie systems, replacing the full-duplex technology of cellular mobile phones.

The term “half-duplex” contrast with “full-duplex”, where information can travel in two directions simultaneously. In a half-duplex system, if one device begins to send data, the other device cannot send its own data until the first has finished transmitting. Due to this limitation, the transmission speed of the system is lower than the speed of a full-duplex system.

The major benefit of half-duplex systems is their cost efficiency. Since one line is used for both transmission and reception, the cost of installation and maintenance is often considerably lower than in a full-duplex system. Additionally, half-duplex technology can be scaled up or down depending on the application, providing greater flexibility and cost savings.

For mission-critical applications, however, half-duplex systems are not the most effective choice. Slow data communication speeds, the inability to send and receive information simultaneously, and the lack of error correction can lead to unpredictable response times. That’s why these systems are most often used in low-priority applications or applications where low-cost is the primary factor.

Overall, half-duplex technology is efficient and cost-effective in certain applications, but limited in comparison to full-duplex systems when it comes to performance and reliability.