54Mbps wireless Ethernet operating in the 5GHz band.

802.11b
The industry standard 11Mbps wireless Ethernet operating at 2.4GHz.

802.11e
Defines quality-of-service for wireless local area networks, to support voice-over IP for example.

802.11g
Successor to 802.11b, providing up to 54Mbps over the same 2.4GHz spectrum used by 802.11b.

802.11h
A supplement to 802.11a to ensure that it meets European regulations on 5GHz wireless local area networks (Lans).

802.11i
Wireless security standard, of which Wireless Protected Access is a subset.

802.11j
Japanese equivalent of 802.11h.

802.11n
A proposed specification to double the speed of 802.11a/g wireless Lan equipment expected in 2006.

802.15
A standard for personal area networks, based on Bluetooth.

802.16
A set of wireless communications standards for high-capacity metropolitan area networks (Mans), otherwise known as WirelessMan and WiMAX.

802.20
Proposal for 1Mbps wireless Mans over distances of up to 15km, intended for operation in licensed bands below 3.5GHz.

802.1x
Authentication scheme based on the Extensible Authentication Protocol.

Access Point
Acts as a hub for wireless Lan clients, usually supporting up to 253 concurrent users over a maximum distance of 100 metres.

Bluetooth
A short-range (10-100 metres) wireless connectivity technology used as a cable replacement for mobile phones, handheld PCs and other peripheral devices. Also used as an alternative to infrared.

Circuit Switched Data
Conventional dial-up method for mobile phone-based data connectivity. Transfer speeds are limited to 9.6Kbps.

Dynamic Frequency Selection/Dynamic Channel Selection
Allows client devices to detect the clearest channels within the radio waveband.

European Telecommunications Standards Institute
Develops telecoms standards in Europe.

Extensible Authentication Protocol
Improves wireless Lan security by allowing the dynamic addition of authentication plug-in modules at both the client and the server ends of a wireless connection.

General Packet Radio Service
An always-available cellular network technology used to provide internet and intranet access via mobile phones at data rates up to 114Kbps. Usual speeds in the UK average 42Kbps.

Global Positioning System
A group of 24 geo-stationary satellites that orbit the Earth and provide positioning and telemetry data to ground receivers to pinpoint their geographical location and travelling speed. The location accuracy is in the range 10-100 metres for most equipment.

High-Speed Circuit Switched Data
A protocol for higher data rates (14.4Kbps) over dial-up mobile data connections.

HiperLAN/1
A competing wireless Lan standard to 802.11b that provides data transmission at up to 20Mbps in the 5GHz spectrum.

HiperLAN/2
HiperLAN variant that operates at up to 54Mbps in the same radio frequency band as HiperLAN/1.

Hotspot
A public access wireless Lan installed in places such as airports, railway stations, hotels and coffee shops. It provides mobile users with high-speed access to the internet using a wireless-equipped laptop or PDA.

Infrared Data Association
An industry-sponsored organisation set up to create and maintain international standards for the hardware and software used in infrared communication links.

Institute of Electrical and Electronics Engineers
The body responsible for the development of 802.11x wireless Lan standards.

Quality of Service statements
A measurement of transmission and error rates, usually used as a measure of network performance for determining network reliability and enforcing service level agreements.

Radiocommunications Agency
Regulates the use in the UK of the 2.4GHz and 5GHz wavebands used by wireless Lan equipment.

Robust Security Network
A WPA replacement built on 802.1x and the Advanced Encryption Standard.

Transport Layer Security
A protocol that ensures privacy between communicating applications and their users over wireless Lans and the internet.

Transmit Power Control
Allows wireless Lan clients to use the minimum output power necessary to transmit data signals if interference with other transmissions is encountered.

Wired Equivalent Privacy
The default encryption scheme used by 802.11x equipment. It comes in 40-bit or 128-bit formats and is considered to be very insecure.

Wireless Ethernet Compatibility Alliance
A trade association created to carry out testing and to promote interoperability across wireless Lan equipment from different vendors.

Wireless Protected Access
A WEP replacement that uses rotating keys to provide more robust security for wireless data connections.

WLan
Short name for wireless Lan, also known as Wi-Fi.

WI-MAX

Wi-MAX (also known as 802.16) technology has been in development since 2001, and is now beginning to appear on the market. It offers data rates on a par with most wired Ethernet networks over a range of about 30 miles.

The technology is seen as a way of delivering large quantities of bandwidth into remote locations or across disparate corporate and campus locations. The Wi-MAX standard has already fragmented into two variants:

• 802.16a The original Wi-MAX standard, which can transfer at up to 70Mbps over distances of as much as 30 miles using the 10GHz and 66GHz spectrums.
• 802.16e A more recent development which will operate in the 2GHz - 6GHz licensed bands, bringing the possibility of mobile devices using the technology.

The fact that the Wi-MAX standard addresses both metropolitan area network implementation and end-user applications makes it a viable consideration for next-generation wireless Lan deployment.

This is because it allows companies to standardise on a single protocol and core technology for site-to-site and site-to-user wireless networking delivery.

Issues regarding the reclassification of the necessary spectrum for domestic and unlicensed commercial use remain a problem in some European, Middle East and Asian countries.

However, as with 802.11a, which faced similar problems, this is expected to be addressed as user demand grows in neighbouring countries.