A switch is a network device used for electrical signal forwarding. It can provide an exclusive electrical signal path for any two network nodes that access the switch. The most common switch is Ethernet switches.
The main functions of a switch include physical addressing, network topology, error checking, frame sequence, and flow control. At present, the switch also has some new functions, such as support for VLAN (Virtual Local Area Network), support for link aggregation, and some even have the function of a firewall.
The transmission modes of the switch are full-duplex, half-duplex, and full-duplex/half-duplex adaptive. The full-duplex of the switch means that the switch can also receive data while sending data, and the two are synchronized. Current switches support full-duplex. The advantage of full-duplex is that the delay is small and the speed is fast.