Wi-Fi Glossary

Wi-Fi Glossary

125 High Speed Mode
54g performance enhancement that delivers the industry’s fastest wireless throughput in real-world environments. It is designed for home networks that require high-speed throughput for multimedia applications, such as sharing digital pictures. (See also: SpeedBooster)

802.11
The standard that defines the technology used for wireless LAN products. The original standard was ratified by the IEEE in 1997, and specified products with a maximum data rate of 2 Mbps. Since then, the standard has expanded to define faster wireless systems. (See also: IEEE, 802.11a, 802.11b, 802.11g, 802.11n)

802.11a
The IEEE standard for wireless LAN products that specifies data rates up to 54 Mbps in the 5 GHz band. 802.11a products are not compatible with those based on 802.11b or 802.11g and their range is approximately half that of 802.11b/g products.

802.11b
The IEEE standard for wireless LAN products that specifies data rates up to 11 Mbps in the 2.4 GHz band. 802.11b was the first widely-accepted Wi-Fi technology, but has now been replaced by the faster 802.11g standard.

802.11e
An IEEE standard that adds Quality of Service (QoS) features and multimedia support to the existing 802.11b, 802.11g, and 802.11a wireless networks. (See also: QoS, WMM)

802.11g
The IEEE standard for wireless LAN products that specifies data rates up to 54 Mbps in the 2.4 GHz band. 802.11g is now the mainstream technology for wireless networks in the home, office and public places.

802.11i
The IEEE standard specifying security mechanisms for 802.11 networks. 802.11i makes use of the Advanced Encryption Standard (AES), and includes improvements in key management, user authentication through 802.1X and data integrity of headers. (See also: AES, WPA2)

802.11n
The forthcoming IEEE standard for wireless LAN products that may specify data rates up to 500 Mbps, and throughput between 100 and 200 Mbps. The 802.11n standard will utilize MIMO technology along with other techniques to improve efficiency, and is expected to be finalized in 2006. (See also: MIMO, Pre-N)

Advanced Encryption Standard (AES)
The preferred standard for the encryption of commercial and government data using a symmetric block data encryption technique. It is specified in the 802.11i security standard and used in the implementation of WPA2. (See also: 802.11i, Encryption, WPA2)

Access Point (AP)
Wi-Fi enabled computers typically connect to wired networks by means of an access point, a wireless device whose primary function is to consolidate multiple wireless connections, serving as an intermediary between wireless devices and high-speed wired networks. Access points are connected to a wired network with an Ethernet cable.

Ad-Hoc
An old term used to describe a device-to-device network in which devices communicate between one another without going through a router or access point (also known as a peer-to-peer network).

Authentication
The process to verify the identity of a wireless client or end user and allow it access to the network.

Bandwidth
The maximum transmission capacity of a communications channel at any time (usually measured in bits per second). If you compare the communications channel to a pipe, bandwidth represents the pipe width and determines how much data can flow through the pipe at any one time.

Bridge
A wireless device that connects multiple networks together. (See also: Wireless Ethernet Transceiver)

Broadband Modem
Broadband modems act as gateways for high speed network access in the home and small business, facilitating a broadband connection through cable or DSL connection. Some broadband modems are beginning to incorporate Wi-Fi capabilities, replacing the need for an access point or router.

Client
Any computer connected to a network that requests files and services from the server or other devices on the network. The term also refers to end users in a network.

Data Rate
Pre-determined rates set in the 802.11 standard that provide for systematic speed decreases to maintain a connection as the client moves farther away from the access point. The OFDM data rates include: 54, 48, 36, 24, 18, 12, 11, 9, 6, 5.5, 2 and 1. This is not the actual speed at which data is sent (called throughput), because of built-in redundancy, error correction, and protocol overhead. (See also: Throughput)

Dual-Band
A device that is capable of operating in two frequencies. On a wireless network, dual-band devices are capable of operating in both the 2.4 GHz (802.11b/g) and 5 GHz (802.11a) bands. In cellular phone technology, dual-band devices typically operate in both the GSM900 and GSM1800 frequencies, allowing a greater number of roaming options.

Encryption
A mechanism for providing data confidentiality. (See also: AES, WPA, WPA2)

Hotspot
A public location where users can access the Internet using Wi-Fi enabled devices. Access may be provided free or for a fee. Hotspots are often found at coffee shops, hotels, airport lounges, train stations, convention centers, and other public meeting areas. Corporations and campuses often offer it to visitors and guests.

IEEE
Institute of Electrical and Electronics Engineers. The IEEE is an international organization that develops standards for hundreds of electronic and electrical technologies. The organization uses a series of numbers (like the Dewey Decimal system) to differentiate between the various technology families. (See also: 802.11)

LAN
Local Area Networks. A system that connects PCs and other devices within the same location in order to share resources such as Internet connections, printers, files and storage drives. When Wi-Fi is used to connect the devices, the system is known as a wireless LAN or WLAN.

MIMO
Multiple Input Multiple Output. A technique that uses multiple receivers and multiple transmitters on both ends of a wireless connection to improve throughput and range. MIMO is expected to be the basis of the forthcoming 802.11n wireless LAN standard. (See also: 802.11n, Pre-N)

MiniPCI
Wireless functionality that is embedded onto the motherboard of the computer, typically installed at the factory, and is not removable or upgradeable.

OFDM
Orthogonal Frequency Division Multiplexing. OFDM is a modulation technique used in the 802.11a and 802.11g standards (previous 802.11b products used a modulation technique known as CCK). In an OFDM system, data transmissions are split among several narrowband channels at different frequencies, which reduces interference by preventing the demodulators from seeing frequencies other than their own.

PC Card
Wireless functionality can be added to notebook computers through the use of a removable network card which is inserted into a type 2 or 3 cardbus slot.

PCI Card
Wireless card that is installed in the PCI bus slot inside desktop PCs.

Pre-N
A name coined by manufacturers delivering non-standard Wi-Fi products that promise increased range and speed. The term “pre-N” is designed to lead consumers to believe that these products might be compatible with, and perform like, future 802.11n products. (See also: 802.11n, MIMO)

Print Server
A wireless print server allows multiple computers and other Wi-Fi enabled devices to share a printer without the use of cables. Print servers are typically connected via parallel or USB port to the printer, and allows files to be transferred wirelessly for printing.

Quality of Service (QoS)
Enables Wi-Fi access points to prioritize traffic and optimize the way shared network resources are allocated among different applications. Without QoS, all applications running on different devices have equal opportunity to transmit data frames. That works well for data traffic from applications such as file transfers or e-mail, but it is inadequate for multimedia applications. QoS is required for multimedia applications (such as VoIP, video streaming, and interactive gaming), which are highly sensitive to latency increases and throughput reductions. (See also: 802.11e, WMM)

Repeater
A device that extends the coverage of an existing access point by relaying its signal.

Router
Wireless routers provide the same functionality as access points, but include the added features of allowing multiple users to share a wide area connection to a broadband modem-providing multiple IP addresses, firewall capabilities, and hub and switching functionality.

SecureEasySetup
A feature that allows people to setup their Wi-Fi network and activate WPA security with the push of a button. SecureEasySetup is currently offered in some models of Wi-Fi products from Linksys, HP and Buffalo.

SpeedBooster
Linksys’ brand of Wi-Fi products that use Broadcom’s 125 High Speed Mode, which increases the throughput of an 802.11g network. (See also: 125 High Speed Mode)

Throughput
The actual speed at which data is transmitted in a wireless network. Because of communication and protocol overhead, throughout is generally less than the data rate. (See also: Data Rate)

USB
Universal Serial Bus (USB) interface cards connect notebook and desktop computers to wireless networks via the client’s USB port, rather than utilizing either embedded mini-PCI or removable PC cards.

WEP
The original security standard used in wireless networks to encrypt the wireless data. Because WEP had many flaws that were easily cracked, it has been replaced by stronger security technologies, such as WPA and WPA2.

Wi-Fi
A term developed by the Wi-Fi Alliance to describe WLAN products that are based on the IEEE 802.11 standards. (See also: Wi-Fi CERTIFIED)

Wi-Fi CERTIFIED
The certification standard designating IEEE 802.11-based WLAN products that have passed interoperability testing requirements developed and governed by the Wi-Fi Alliance. (See also: Wi-Fi)

Wi-Fi Alliance
A non-profit organization that certifies the interoperability of 802.11 wireless LAN products. Products bearing the Wi-Fi CERTIFIED logo have been proven to work with Wi-Fi products from other vendors. The Alliance also makes sure that certain security and performance features are interoperable, to improve the Wi-Fi user experience.

Wi-Fi Multimedia (WMM)
A group of features that improves the user experience for audio, video and voice applications on wireless networks. Based on the IEEE 802.11e draft standard, WMM adds prioritization capabilities to Wi-Fi networks and optimizes their performance when multiple concurrent applications, each with different latency and throughput requirements, compete for network resources. (See also: 802.11e, QoS)

WiMax
The common name for the forthcoming IEEE 802.16 standard. Wi-Max is will provide last-mile wireless broadband access to areas in which cable or DSL are not feasible. For additional information, visit http://www.wimaxforum.org/home.

Wireless Ethernet Transceiver (WET)
Allows you to convert an Ethernet- based device into a wireless device by connecting the wireless transceiver/bridge to an Ethernet Port. (See also: Bridge)

WPA
Wi-Fi Protected Access. A security standard that uses the latest encryption and authentication technologies to provide strong data protection and network access control for wireless networks. WPA was designed to secure all 802.11 devices, and can be found on all 802.11b, 802.11a and 802.11g products that are Wi-Fi CERTIFIED. (See also: Encryption)

WPA2
Wi-Fi Protected Access 2, also known as 802.11i. The latest security method that provides even greater data protection and network access control for wireless networks. The primary difference is that WPA2 uses the government-grade AES encryption algorithm and 802.1X-based authentication, which are required to secure large corporate networks. (See also: 802.11i, AES, Encryption)

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