IEEE 802.11 (WiFi) bands a b g n

IEEE 802.11 is a set of measures bearing out wireless localized locality mesh (WLAN) computer connection in the 2.4, 3.6 and 5 GHz frequency bands. They are conceived and sustained by the IEEE LAN/MAN Standards Committee (IEEE 802). The groundwork present type of the benchmark is IEEE 802.11-2007.

The 802.11 family encompasses over-the-air modulation methods that use the identical rudimentary protocol. The most well liked are those characterised by the 802.11b and 802.11g protocols, which are amendments to the initial standard. 802.11-1997 was the first wireless networking benchmark, but 802.11b was the first broadly acknowledged one, pursued by 802.11g and 802.11n. Security was initially purposefully feeble due to trade items obligations of some authorities, and was subsequent increased by the 802.11i amendment after governmental and legislative changes. 802.11n is a new multi-streaming modulation technique. Other measures in the family (c-f, h, j) are service amendments and additions or amendments to the preceding specifications.

802.11b and 802.11g use the 2.4 GHz ISM band, functioning in the United States under Part 15 of the US Federal Communications Commission Rules and Regulations. Because of this alternative of frequency band, 802.11b and g gear may rarely bear interference from microwave ovens, cordless telephones and Bluetooth devices. 802.11b and 802.11g command their interference and susceptibility to interference by utilising direct-sequence disperse spectrum (DSSS) and orthogonal frequency-division multiplexing (OFDM) indicating procedures, respectively. 802.11a values the 5 GHz U-NII band, which, for much of the world, boasts at smallest 19 non-overlapping passages other than the 3 suggested in the 2.4 GHz ISM frequency band. Better or poorer presentation with higher or smaller frequencies (channels) may be recognized, counting on the environment.

The segment of the radio frequency spectrum utilised by 802.11 varies between countries. In the US, 802.11a and 802.11g apparatus may be functioned without a permit, as permitted in Part 15 of the FCC Rules and Regulations. Frequencies utilised by passages one through six of 802.11b and 802.11g drop inside the 2.4 GHz amateur radio band. Licensed amateur wireless operators may function 802.11b/g apparatus under Part 97 of the FCC Rules and Regulations, permitting expanded power yield but not financial content or encryption.

History

802.11 technologies has its sources in a 1985 ruling by the U.S. Federal Communications Commission that issued the ISM band for unlicensed use.

In 1991 NCR Corporation/AT&T (now Alcatel-Lucent and LSI Corporation) created the forerunner to 802.11 in Nieuwegein, The Netherlands. The inventors primarily proposed to use the expertise for cashier systems; the first wireless goods were conveyed on the market under the title WaveLAN with raw facts and numbers rates of 1 Mbit/s and 2 Mbit/s.

Vic Hayes, who held the seating of IEEE 802.11 for 10 years and has been called the "father of Wi-Fi" was engaged in conceiving the primary 802.11b and 802.11a measures inside the IEEE.

802.11-1997 (802.11 legacy)

The initial type of the benchmark IEEE 802.11 was issued in 1997 and clarified in 1999, but is today obsolete. It particular two net bit rates of 1 or 2 megabits per ...