802.11 the IEEE , 1997, the original standard (2Mbit / s, the broadcast 2.4GHz). DSSS , FHSS . A major drawback of this agreement is that it provides too many choices make interoperability difficult to achieve . So it is not tight, more like a beta standard, different vendors to a lot of flexibility, but the lack of interoperability between vendors.
802.1 la the IEEE , 1999, supplemented physical layer (54Mbit / s, in the broadcast 5GHz). OFDM . 802.11a standard uses the same core as the original standard protocols, operating frequency is 5GHz, the maximum raw data rate of 54Mb / s. 802.11a product sales in 2001, even later than 802.11b products, because 5GHz components of successful development of products is too slow.
802.11b the IEEE , 1999, supplemented physical layer (11Mbit / s, in the broadcast 2.4GHz). DSSS . Mainstream
802.11g the IEEE , 2003, supplemented physical layer (54Mbit / s, in the broadcast 2.4GHz). OFDM , DSSS . Mainstream
802.1 In the IEEE , improve the higher transmission rate, base rate raised to 72.2Mbit / s, can be double the bandwidth of 40MHz, this time rate up to 150Mbit / s. Technology supports multiple input multiple output (the Multi-the Multi-the Output the Input, the MIMO ).