Ethernet switch is a kind of switch that transmits data based on Ethernet, and Ethernet is a way of sharing bus transmission media. The structure of the Ethernet switch: each port of the Ethernet switch is directly connected to the host, and generally in the full-duplex mode. The switch can also connect multiple pairs of ports at the same time, so that each pair of hosts communicating with each other can transmit data without conflict. Ethernet switch is also the most popular application, and the price is relatively cheap. Therefore, the application field is very wide, and Ethernet switches can be seen in large and small LANs. Ethernet switches usually have several to dozens of ports. In essence, it is a multi-port network bridge. In addition, its port rate can be different, and its working mode can also be different, such as providing 10M and 100M bandwidth, providing half-duplex, full-duplex, and adaptive working modes. The principle of Ethernet switch: Ethernet switch is a machine at the data link layer. Ethernet uses physical address (MAC address), 48 bits, and 6 bytes. Its working principle is that when a broadcast frame is received, it will forward it to all ports except the receiving port. When a unicast frame is received, check its destination address and corresponding to its MAC address table. If there is a destination address, it will be forwarded. If it does not exist, it will be flooded (broadcast). After broadcast, if there is no host whose MAC address is the same as the destination MAC address of the frame, it will be discarded. If there is a host whose MAC address is the same, it will be automatically added to its MAC address table.
