Work order, half duplex and full duplex

Based on the division of labor between the two parties and the signal transmission direction, the communication can be divided into three modes: Single-work, half-duplex and full-duplex. In computer networks, the dual mode is used. The LAN adopts the half-duplex mode, and the man and Wan adopt the full dual-year mode. 1. Ticket (simplex): the sender and receiver in the Communication Equipment of both parties have a clear division of labor and can only transmit data in a single fixed direction from the sender to the receiver. Typical sending devices such as card readers of early computers and typical receiving devices such as printers communicate with each other. 2. Half Duplex (halfduplex) mode: both devices on both sides of the communication are both transmitters and receivers. The two devices can transmit data to each other, but data can only be transmitted to one direction at a time. For example, a walkie talkie is a half-duplex device, because only one party can speak at a time. 3. Full Duplex (fullduplex) mode: the communication device is both a transmitter and a receiver, and the two devices can transmit data in both directions at the same time. For example, the phone is a full-duplex device because both parties can talk at the same time.