IEEE 802.11 Standards

The WiFi Family

WiFi isn’t one thing. It’s a family of standards, each identified by a letter. Over time, each new version brought faster speeds, better range, or new technologies.

802.11 is the IEEE standard. The letter after it (a, b, g, n, ac, ax) tells you which version.


802.11b (1999) — The First Popular WiFi

This is where WiFi took off.

  • Frequency: 2.4 GHz
  • Max speed: 11 Mbps
  • Range: Good (2.4 GHz travels far)

The catch: 2.4 GHz is a crowded band. Microwaves, Bluetooth, baby monitors, and your neighbor’s WiFi all compete for the same space.


802.11a (1999) — The Road Not Taken

Released the same year as 802.11b, but took a different approach.

  • Frequency: 5 GHz
  • Max speed: 54 Mbps
  • Range: Shorter (5 GHz doesn’t penetrate walls as well)

Why it didn’t win: More expensive, shorter range. Most people chose 802.11b instead.

But 5 GHz would come back later — it has less interference and more available channels.


802.11g (2003) — Best of Both Worlds

Combined the best parts of a and b.

  • Frequency: 2.4 GHz (good range, like b)
  • Max speed: 54 Mbps (fast, like a)
  • Backward compatible with 802.11b devices

This became the new standard for home routers.


802.11n (2009) — MIMO Changes Everything

The biggest leap forward. This is when WiFi got serious.

  • Frequency: Both 2.4 GHz and 5 GHz
  • Max speed: Up to 600 Mbps
  • Key innovation: MIMO (multiple antennas)

What MIMO added:

  • Multiple streams sent simultaneously
  • Up to 4x4 antenna configurations
  • Wider channels (40 MHz instead of 20 MHz)

802.11n was the first WiFi standard to use MIMO. This is why “Wireless N” routers have multiple antennas sticking out.


802.11ac (2013) — Gigabit WiFi

Pushed speeds into gigabit territory.

  • Frequency: 5 GHz only
  • Max speed: Up to 6.9 Gbps (theoretical)
  • MIMO: Up to 8x8
  • Channel width: 80 MHz or 160 MHz

New feature — MU-MIMO:

  • Multi-User MIMO
  • Router can talk to multiple devices at once
  • Previous standards: one device at a time

802.11ax / WiFi 6 (2019) — Efficiency First

Not just about raw speed. Focused on handling crowds better.

  • Frequency: Both 2.4 GHz and 5 GHz
  • Max speed: Up to 9.6 Gbps
  • Key innovation: OFDMA (borrowed from cellular)

Why it matters:

  • Better performance in crowded places (airports, stadiums)
  • More efficient use of spectrum
  • Lower latency

WiFi 6 uses the same OFDMA technology as 4G/5G cellular networks.


Quick Comparison

StandardYearFrequencyMax SpeedKey Feature
802.11b19992.4 GHz11 MbpsFirst popular WiFi
802.11a19995 GHz54 MbpsLess interference
802.11g20032.4 GHz54 MbpsBest of a + b
802.11n20092.4 / 5 GHz600 MbpsMIMO
802.11ac20135 GHz6.9 GbpsMU-MIMO, wide channels
802.11ax20192.4 / 5 GHz9.6 GbpsOFDMA

Setting Up a WiFi Router (802.11g Example)

Basic steps to configure a wireless router:

  1. Connect to the router (via Ethernet or default WiFi)
  2. Access admin panel (usually 192.168.0.1 or 192.168.1.1)
  3. Set SSID — the network name people will see
  4. Choose channel — pick one with less interference (1, 6, or 11 for 2.4 GHz)
  5. Select security — use WPA2 (never WEP)
  6. Set password — strong, unique passphrase
  7. Save and reboot

Tip: For 2.4 GHz, channels 1, 6, and 11 don’t overlap with each other. Pick one of these to minimize interference from neighbors.