802.11 (1997)

After discussion and debate (dating back to the early 1990s), the “original” 802.11 specification was ratified in 1997. Data rates of 1 or 2 megabits per second (Mbps) were supported. The protocol covers Layer 1 (physical) and Layer 2 (data link) of the OSI model. At the data link layer, 802.11 provides definitions for the following services:

• Authentication/Deauthentication

• Association/Disassociation/Reassociation

• Privacy (WEP)

• Mac Service Data Unit (MSDU) delivery

Three different methods were specified at the physical layer:

• Direct Sequence spread spectrum (DSSS)

• Frequency Hopping spread spectrum (FHSS)

• Infrared (IR)

Most people are not aware that the 802.11 protocol actually included support for IR. Although 801.11 over IR is technically defined and possible, no significant commercial products were ever developed.

In 1999, two high data rate extensions, called 802.11a and 802.11b, were ratified. 802.11g was added in 2003. These standards supported faster speeds (11Mbps for 802.11b and 54 Mbps for 802.11a/g). More on those in a moment.