In the early 21st century, wireless LANs became popular in homes and small businesses as a way to connect computers and other devices to each other and to the Internet without the need for cables. Wireless LANs use radio waves instead of wires to communicate between devices. They are also sometimes called Wi-Fi, which is short for Wireless Fidelity.
A wireless LAN consists of three parts: an access point, client adapters, and a distribution system. The access point is a device that connects the wireless LAN to a wired network such as the Internet or an organization’s intranet. Client adapters are installed in computers and other devices that will be part of the wireless LAN. The distribution system distributes power and data signals from the access point to the clients.
The radio waves used by a wireless LAN travel through walls and ceilings but can be blocked by metal objects such as filing cabinets or refrigerators. The range of a typical home or small office wireless LAN is about 30 meters (100 feet). Larger buildings may have multiple access points to extend the range of theLAN throughout the building.
Wireless LANs operate in one of two frequency bands: 2.4 gigahertz (GHz) or 5 GHz. Most home and small office routers support both bands, but some only support one band orthe other. The 2.4 GHz band is more crowded than 5 GHz because it is also used by Bluetooth devices, cordless phones, baby monitors, garage door openers, and many other typesof consumer electronics products; as a result, 2.4 GHz Wi-Fi networks are more likely than 5 GHz networks to experience interference from these other devices