Wi-Fi

Wi-Fi is a set of standards for wireless networks based on the IEEE 802.11 Wireless Ethernet standards. Wi-Fi was intended to be used for wireless LANs, but is now often also used for Internet access.

Wi-Fi (for "Wireless Fidelity") is a trademark of the Wi-Fi Alliance (formerly the Wireless Ethernet Compatibility Alliance), the trade organization that defines the Wi-Fi standards.

There are at least two types of Wi-Fi, each based on an IEEE 802.11 standard.

IEEE 802.11b enjoy international acceptance because the 2.4-GHz band is almost universally available.
In the United States IEEE 802.11a, which operates around 5 GHz, enjoys relatively clear-channel operation. In other areas, such as the EU, 802.11a is not yet approved for operation in the 5 GHz band, and European regulators are still considering the use of the European HIPERLAN standard.

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 SocketIP and Symbol Technologies are offering telephony platforms (Central Office replacements and terminals (phones)) that use Wi-Fi transport.