Legacy Wi-Fi (802.11a/b/g)
Wi-Fi · 7 specs
Direct Answer
Legacy IEEE 802.11 standards (802.11b, 802.11a, and 802.11g) established commercial consumer wireless networking between 1999 and 2003, transitioning from 11 Mbps DSSS/CCK in the 2.4 GHz band to 54 Mbps OFDM modulation across both 2.4 GHz and 5 GHz bands.
Source: IEEE 802.11-1999 / IEEE 802.11a-1999 / IEEE 802.11b-1999 / IEEE 802.11g-2003 · Last reviewed Aug 28, 2026
Specs
| Standards Included | 802.11b (1999), 802.11a (1999), 802.11g (2003) |
| Frequency Bands | 2.4 GHz (802.11b/g), 5 GHz (802.11a) |
| Max Data Rate (802.11b) | 11 Mbps |
| Max Data Rate (802.11a/g) | 54 Mbps |
| Max Channel Width | 20 MHz |
| Modulation Schemes | DSSS / CCK (802.11b), OFDM (802.11a/g) |
| Spatial Streams (MIMO) | 1 (SISO only) |
Evolution from 802.11b to 802.11g
IEEE 802.11b (1999) popularized home wireless by utilizing the unlicensed 2.4 GHz ISM band at speeds up to 11 Mbps using Direct-Sequence Spread Spectrum (DSSS) and Complementary Code Keying (CCK).
802.11a introduced Orthogonal Frequency-Division Multiplexing (OFDM) in the clean 5 GHz band at 54 Mbps, but suffered shorter range and higher manufacturing costs. In 2003, 802.11g brought 54 Mbps OFDM to 2.4 GHz, maintaining backward compatibility with 802.11b hardware while vastly improving real-world throughput.
Historical Wi-Fi Naming Context
Before the Wi-Fi Alliance introduced numerical naming (Wi-Fi 4, 5, 6, 7) in 2018, these original generations were known solely by their IEEE letter suffixes.