Introduction to (the history of Wifi)

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The 802.11 standard defines a link layer wireless protocol and is managed by the Institute of Electrical and Electronics Engineers (IEEE). Many people think of Wi-Fi when they hear 802.11, but they are not quite the same thing. In recent years, Wi-Fi and 802.11 have exploded in popularity, and every new laptop comes with a builtin Wi-Fi adapter. This popularity has led to a surge of research into the security of the 802.11 standard.

The history about the first 802.11 standard was approved in 1997 and allowed transmission speeds that topped out at 2 Mbps. This version of the standard allowed two different methods for encoding information at a physical level, Frequency Hopping Spread Spectrum (FHSS) and Direct Sequence Spread Spectrum (DSSS). These two different encoding schemes are incompatible, however, and the choice led to a lot of confusion in the marketplace.


In 1999, the IEEE released 802.11b, an amendment to the original 802.11 standard. The 802.11b standard used DSSS and increased the maximum transmission speed to a much faster 11 Mbps. Also released in 1999 was 802.11a, which allowed 802.11 to run outside of the crowded 2.4-GHz industrial, scientific, and medical (ISM) band and in the 5-GHz Unlicensed National Information Infrastructure (UNII) band. Due to increased cost and reduced signal propagation, 802.11a was never widely adopted by consumers despite the increased speed it offered (54 Mbps).

Increasing the speed of 802.11 has been a consistent priority for the 802.11 committee, so in 2003, they released another speed boost, 802.11g, which brought 54 Mbps while also utilizing the 2.4-GHz band. The next speed increase is 802.11n, which allows speeds of 100 Mbps.

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