Unit 20
Chapter 14
WiFi Standards
The world of WiFi changes fast, fast, fast. We’ve gotten used to calling different types of WiFi things like 802.11g and 802.11ac, but this system has gotten non-techies so confused the the WiFi Consortium has standardized on a simpler terminology: 802.11ax, for instance, is officially WiFi 6.
CompTIA says there are two modes of Wifi:
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- Infrastructure Mode
- Ad Hoc Mode
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There’s actually a difference between peer-to-peer and ad hoc, but not as far as this test goes.
Ad Hoc mode is disabled by default in Windows 8+, but can be enabled at the command line.
Standard | Wifi Version | Freq | Encr. | Speed | Beams | M.plex |
---|---|---|---|---|---|---|
802.11 (“legacy mode”) |
none | 2.4 GHz | – | 1-2 Mbps | 1 | keyboards, mice |
802.11a | WiFi 1 | 5 GHz | – | 54 Mbps | 1 | – |
802.11b | WiFi 2 | 2.4 GHz | WEP | 11 Mbps | 1 | – |
802.11g | WiFi 3 | 2.4 GHz | WPA | 54 Mbps | 1 | – |
802.11n | WiFi 4 | 2.4 GHz, 5 GHz | WPA2 – PSK, Enterprise | ~300 Mbps | 4 | MIMO |
802.11ac | WiFi 5 | 5 GHz | WPA3 – PSK, Enterprise | ~300 Mbps | 8 | MU-MIMO, OFDM |
802.11ax | WiFi 6 | 2.4 GHz, 5 GHz | WPA3 – PSK, Enterprise | ~300 Mbps | 8 | MIMOA, OFDMA |
802.11ax | WiFi 6e | 6 GHz | WPA3 – PSK, Enterprise | ~300 Mbps | 8 | MIMOA, OFDMA |
Wi-Fi HaLow
Low power, long range Wi-Fi® for IoT
https://www.wi-fi.org/discover-wi-fi/wi-fi-halow
Authentication and Encryption Standards
These aren’t the same as the WiFi protocol standards above. These standards control how devices authenticate to a WiFi network, and how they encrypt their traffic.
WEP
The original WiFi “security” protocol was WEP, so-called “wireless equivalent privacy”. It sucked, and its name was a lie. It used wimpy RC4 stream encryption, and cracking encryption keys was a simple game.
WPA
WPA, WiFi Protected Access, was better. It still relied on RC4, but it did the clever trick of changing the encryption key very frequently using TKIP. By the time you cracked a key, it wasn’t the key anymore. But this just invited a race.
WPA2
WPA2 moved to AES encryption, with pre-shared key (PSK) and Enterprise (meaning directory login, often involving certificates).
https://www.lifewire.com/what-is-wpa2-818352
But WPA2 became more susceptible as password hash (key) cracking moved onto ultra-fast GPUs.
WPA3
Thus came WPA3. Here’s technical details at the Wikipedia level:
Wi-Fi Protected Access: https://en.wikipedia.org/wiki/Wi-Fi_Protected_Access#WPA3
And here’s a more friendly PC Magazine article:
WPS
So … Wifi Protected Setup is yet another lie. It’s used two ways: by pushing a button labelled “WPS” on your WAP, and for five minutes anyone can join. Think about that.
Or, you can use an 8-digit PIN number to invoke WPS over the air. 8 digits. Think even harder about that, and how fast such a PIN could be cracked.