Wi-Fi Alliance
Wi-Fi (pronounced "why-phy") is a trade
name developed by WFA and has come to mean WLAN for many users. The group is
responsible for the term Wi-Fi (which is meant to
be a truncation of wireless fidelity) and, more importantly, independent testing
to verify interoperability.
Wi-Fi describes WLAN products that are based on IEEE 802.11
standards and is meant to be a more user-friendly name in the same way that
Ethernet and Token Ring are more user friendly than IEEE 802.3 and 802.5,
respectively. No other organization has done so much to drive the adoption of
the WLAN technologies. With the goal of interoperability among devices based on
the 802.11b standard, the WFA started a program to certify interoperability
among devices. Founded in August 1999 by 3Com, Aironet Wireless Communications,
Harris Semiconductor (now Intersil), Lucent Technologies (later Agere), Nokia,
and Symbol Technologies, the WFA has grown to well over 200 members. Products
such as bar code scanners, PCMCIA cards, embedded radio modules, APs, and
wireless entertainment systems have successfully passed Wi-Fi interoperability
testing and earned the right to carry the Wi-Fi label.
The Wi-Fi certification label ensures customers of at least a
base level of interoperability. Wi-Fi testing, which is conducted at a
third-party testing lab, is fairly stringent.
Other Wi-Fi Certifications
Other testing has also started to take place at the WFA. There
is now a security specification called Wi-Fi Protected
Access (WPA) that follows the 802.11i security specification
and provides a test to ensure interoperability among devices when using WPA.
There is also a QoS interoperability certification available
from WFA, known as Wi-Fi Multimedia (WMM), which uses some features identified
by the 802.11e task group.
Wi-Fi Capabilities Label
Originally, Wi-Fi was meant to
describe only 11-Mbps (maximum) devices that operate in the 2.4-GHz portion of
the frequency spectrum and that conform to the IEEE 802.11b specification. It
was later decided that Wi-Fi should be expanded to include 54-Mbps (maximum)
data rate products operating in both the 2.4-GHz and 5-GHz portions of the
frequency spectrum that are based on the IEEE 802.11g and 802.11a
specifications. Testing for all three technologies provides for certification in
all areas but creates some confusion for the customer.
Today a Wi-Fi device carries a Wi-Fi
certification logo, and the packaging also carries a capabilities label (see Figure 1-4). This label defines which
certification the device has passed, such as 802.11a, 802.11b, WPA, and so on. A
customer implementing a multivendor WLAN network is advised to demand that all
devices in the WLAN have passed interoperability testing and verification and
have received the Wi-Fi logo.
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