Wireless LAN:

 AWLAN provides wireless network communication over short distances using radio or infrared signals instead of traditional network cabling. A WLAN typically extends an existing wired local area network. WLANs are built by attaching a device called the access point (AP) to the edge of the wired network. Clients communicate with the AP using a wireless network adapter similar in function to a traditional Ethernet adapter. Network security remains an important issue for WLANs. Random wireless clients must usually be prohibited from joining the WLAN. Technologies like WEP raise the level of security on wireless networks to rival that of traditional wired networks. A wireless LAN (or WLAN, for wireless local area network, sometimes referred to as LAWN, for local area wireless network) is one in which a mobile user can connect to a local area network (LAN) through a wireless (radio) connection. The IEEE 802.11 group of standards specify the technologies for wireless LANs. 802.11 standards use the Ethernet protocol and CSMA/CA(carrier sense multiple access with collision avoidance) for path sharing and include an encryption method, the Wired Equivalent Privacy algorithm. (Wireless Local Area Network) A communications network that provides connectivity to wireless devices within a limited geographic area. "Wi-Fi (Wireless fidelity)" is the universal standard for wireless networks and is the wireless equivalent of wired Ethernet networks. In the office, Wi-Fi networks are adjuncts to the wired networks. At home, a Wi-Fi network can serve as the only network since all laptops and many printers come with Wi-Fi built in, and Wi-Fi can be added to desktop computers via USB. Wi-Fi is achieved with a wireless base station, called an "access point." Its antennas transmit and receive a radio frequency within a range of 30 to 150 feet through walls and other non-metal barriers. The key hardware components of a wireless computer network include adapters, routers and access points, antennas and repeaters. Wireless network adapters (also known as wireless NICs or wireless network cards) are required for each device on a wireless network. All newer laptop computers incorporate wireless adapters
as a built-in feature of the system. Separate add-on adapters must be purchased for older laptop PCs; these exist in either PCMCIA"credit card" or USB form factors. No wireless hardware other than adapters is required to build a small local network. However, to increase the performance of network connections, accommodate more computers, and increase the network's range, additional types of hardware can be deployed such as routers and access points, antennas and repeaters.