A switch is a hardware component in network infrastructure that performs the switching process. The switch connects network devices, such as computers and servers, to one another.

A switch enables multiple devices to share a network while preventing each device’s traffic from interfering with other devices’ traffic. The switch acts as a traffic cop at a busy intersection. When a data packet arrives at one of its ports, the switch determines which direction the packet is headed. It then forwards the packet through the correct port for its destination.

Some data packets might come to the switch from devices, like computers or voice-over-IP (VoIP) phones, that are attached directly to it. Other data packets might come to the switch from indirectly connected devices, through a network element such as a hub or router.

The switch knows which of the network’s devices are connected to it, and it can transfer data packets between those devices directly. In other cases, data packets may be going to more-distant destinations, on other networks. A switch in such a scenario forwards the packets to a router, which then forwards them to their destinations on the network.