What is the function of a switch in a network?

The primary function of a switch in a network is to connect devices within a local area network (LAN). Switches operate at the data link layer (Layer 2) of the OSI model and use MAC addresses to forward data to the correct destination within that network. This enables efficient communication between devices such as computers, printers, and servers that are all part of the same local area network.

By managing data flow and reducing collisions through a method known as frame switching, switches enhance the overall performance of the network. Each port on a switch serves as a dedicated channel for connected devices, allowing them to communicate simultaneously without interfering with each other. This capability is fundamental in maintaining network efficiency in environments with multiple devices.

In contrast, the other options refer to functions not typical for switches. Connecting devices across different networks usually involves routers, while wireless access points focus on providing a wireless network connection rather than switching functions. Filtering network traffic can be a feature of switches equipped with advanced capabilities, but it is not the primary role of standard switches in a LAN setup. Thus, the assertion that a switch connects devices on a LAN accurately describes its essential function.