Use the pull-down menu to the left to select a term that you would like defined. Or, scroll through our selection of technical terms and their definitions, listed in alphabetical order.
 

Access Point (AP)

Transports data between a wireless network and a wired network (infrastructure).

Direct sequence

A method of wireless transmission that can provide higher data rates and greater robustness in radio-noisy environments than frequency hopping. The trade-off is higher cost and fewer users for a given area.

IEEE 802.X

A set of specifications for Local Area Networks (LAN) from the Institute of Electrical and Electronic Engineers (IEEE). Most wired networks conform to 802.3, the specification for CSMA/CD based Ethernet networks. The 802.11 committee completed a standard for 1 and 2 Mbps wireless LANs in 1997 that has a s ingle MAC layer for the following physical-layer technologies: Frequency Hopping Spread Spectrum, Direct Sequence Spread Spectrum, and Infrared. IEEE 802.11 HR, is an 11 Mbps version of the standard.

Independent network

A network that provides (usually temporarily) peer-to-peer connectivity without relying on a complete network infrastructure.

Infrastructure network

A wireless network centred around an AP. In this environment, the AP not only provides communication with the wired network but also mediates wireless network traffic in the immediate neighbourhood.

ISM band

Industrial, Scientific and Medical Band. A set of radio frequencies centred around 2.4 GHz which are universally acknowledged to be available for use by wireless technologies.

MAC layer

The Media Access Control layer of networking - in other words, the circuitry (usually a network interface card) that manages access to the physical layer of the network. This is typically the cable or fibre but can also refer to a wireless link.

Microcell

A bounded physical space in which a number of wireless devices can communicate. Because it is possible to have overlapping cells as well as isolated cells, some rule or convention establishes the boundaries of the cell.

NIC

A Network Interface Card.

PC Card

Types of cards that can be plugged into the PC Card slot found in some computers - most typically notebooks - with the aim of adding extra functionality, such as networking.

PPP

Point-to-Point Protocol - a means of setting up a two-ended link using the Internet Protocol (IP).

Protocol

A kind of language that two or more devices have in common and which thereby allows them to intercommunicate. The best-known example is the Internet Protocol (IP), which all devices connected to the Internet must use in order to exchange information.

Radio Frequency (RF) Terms: GHz, MHz, Hz

The international unit for measuring frequency is Hertz (Hz), which is equivalent to the older unit of cycles per second. One Megahertz (MHz) is one million Hertz. One Gigahertz (GHz) is one billion Hertz. For reference: the standard US electrical power frequency is 60 Hz, the AM broadcast radio frequency band is 0.55 -1.6 MHz, the FM broadcast radio frequency band is 88-108 MHz, and microwave ovens typically operate at 2.45 GHz.

Roaming

Movement of a wireless node between two microcells. Roaming usually occurs in infrastructure networks built around multiple APs.

Wireless LAN (WLAN)

A Local Area Network whose physical layer - i.e. the cabling - has been replaced by radio waves.

Wireless node

A user computer with a wireless network interface card (NIC).