1. Standard 802.11

The first version of the 802.11 standard dates back to 1997. In 1999, two extensions, a and b, were added .

The initial standard defines three physical layersPHY (PHYsical) and a layer for controlling access to the transmission medium MAC (Medium Access Control). One of the PHY layers uses Infra Red (IR) waves, enabling data rates of up to 2 Mbit/s. The other two layers use 2.4 GHz radio waves, one with Direct Sequence Spread Spectrum (DSSS) and the other with Frequency Hopping Spread Spectrum (FHSS), both of which enable data rates of up to 2 Mbit/s. Extensions a and b respectively define a PHY OFDM (Orthogonal Frequency Division Multiplexing) layer...