The IEEE 802.11 Standard

In 1990, the IEEE formed a committee to develop a standard for wireless
LANs, operating at 1 and 2 Mbps. For several reasons, but most importantly
due to the existence in the market of different LAN products made by the corresponding
manufacturers, the first of the standards took seven years to see
the light of day. The IEEE 802.11 system [2] was approved in 1997, allowing
work at data rates of 1 and 2 Mbps. In the fall of 1999, the standard was
extended to break the 10-Mbps barrier [3]. Thus, the IEEE 802.11b was
born, allowing reaching data rates of 5.5 Mbps and 11 Mbps. In parallel to
this activity, a second group was working on a standard working in the
5-GHz band. This standard, known as IEEE 802.11a, allowed work at velocities
of 6, 12, and 24 Mbps defining 9, 18, 36, and 54 Mbps as options [4].
Currently, the IEEE 802.11 standard body Task Group G is considering
an even higher rate extension, for 11b networks, that will supply a payload
rate in excess of 20 Mbps maintaining compatibility. Finally, the main
standard-setting activities of the IEEE 802.11 committee involve enhancements
to the MAC, 11e (quality of service), and 11i (security), along with
the previously mentioned increase in velocity with respect to the existing
standard, 11g.