Wi-Fi
Wi-Fi (or WiFi, Wifi, wifi), for "Wireless Fidelity", is a set of standards for wireless local area networks (WLAN) based on the IEEE 802.11 specifications (see also that article). Certified products can use the official Wi-Fi logo, which indicates that the product is interoperable with any other product also showing the logo.
Wi-Fi was intended to be used for wireless LANs, but is now often also used for Internet access. It enables a person with a wireless-enabled computer or personal digital assistant (PDA) to connect to the Internet by moving within, for example, 15 meters of an access point, called "hotspot".
Some argue that Wi-Fi and related consumer technologies hold the key to replacing cellular telephone networks such as GSM. Some obstacles to this happening in the near future are missing roaming and authentication features (see 802.1x, SIM cards and RADIUS) and the narrowness of the available spectrum. Despite such problems, companies like Zyxel, SocketIP and Symbol Technologies are offering telephony platforms (Central Office replacements and terminalss (phones)) that use Wi-Fi transport.
The term 4G is occasionally used for Wi-Fi, the implication being that the bandwidth and capabilities offered are already greater than those promised by the 3G cellular telephone standards.
Areas with Wi-Fi service are called "hotspots" and can either be accessed for free or for a fee. There may be metered access or with a pass for, for example, a day, month or year, valid for one location or a whole chain. They are e.g. in coffee houses and airports around the world. T-Mobile provides hotspots in many Starbucks Coffee houses in the US. Pacific Century Cyber Works has a similar arrangement with Pacific Coffee in Hong Kong. Other large hotspot providers in the US include Boingo, Wayport and iPass. Compared to cellular, however, even the combined coverage is currently still very patchy.
Sify, India's largest Internet service provider, has set up 120 wireless access points in Bangalore in hotels, malls and government offices.
Compare Internet cafe.
Not a lot of Wi-Fi hardware is supported by the Linux kernel.
Wi-Fi is a trademark of the Wi-Fi Alliance (formerly the Wireless Ethernet Compatibility Alliance), the trade organization that defines the Wi-Fi standards.
Many business and residential users do not bother to protect their network, which can therefore also be used by people just outside the building, see warchalking and wardriving.
Wi-Fi vs. cellular
Commercial Wi-Fi
Advantages of Wi-Fi
Disadvantages of Wi-Fi
Wi-Fi and free software
Trademark
Unintended use by outsiders
See also
External links
Adapters with free, open drivers