802.11b (or 802.11b-1999) is an evolution of the IEEE (Institute of Electrical and Electronic Engineers) standard that raised transmission rates to 11 Mbit/s using the prior 2.4 GHz band. 802.11b is the system used in WLANs (Wireless Local Area Networks) marketed under the name ‘Wi-Fi’ and implemented around the globe. Wi-Fi is often expanded (albeit erroneously) to mean ‘Wireless Fidelity.’ 802.11b is compatible with its predecessor and root model 802.11.

802.11 is a group of IEEE standards used to govern methods for transmission in wireless networks. The most commonly used versions of the series today are 802.11a, the 802.11b, and the 802.11g. This group offers wireless connectivity for home, office, and commercial computer use.

802.11b employs the Ethernet protocol, as well as the CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) method for purposes of file sharing, following 802.11 standards. PSK (phase-shift keying) is the method of modulation used by most of the 802.11 devices, while 802.11b uses CCK (complementary code keying). The latter standard allows faster and higher data transmission and less multipath propagation obstructions.

802.11b uses the standard media access methods. In early 2000, 802.11b products emerged in the market, acquiring a direct modulation adjustment used by 802.11. A radical increase in transmission rates and the significant price reduction of the 802.11b version (as compared to the original 802.11) led to its present popular reputation in the WLAN technology world.

IEEE 802.11b-compatible equipment may bring about interference when used near products operating within the 2.4 GHz frequency range. These devices include baby monitors, Bluetooth devices, cordless phones, and microwave ovens.