Wi-Fi a.k.a. IEEE 802.11 Technology
Wi-Fi. You know it. You curse it. It's the thing that connects everything when it works, and ruins meetings when it doesn’t. Based on IEEE 802.11, it was never meant for IoT, but here we are – trying to squeeze sensors into an airport-grade protocol. Not LPWAN. Not fancy. Not simple. But it’s everywhere and somehow still alive.
Vendor and URL
This glorious mess is pushed by:
Main vendor: Wi-Fi Alliance / IEEE
Official docs: https://www.wi-fi.org
If the link’s dead, blame your access point firmware. Or IEEE for drowning in PDFs.
Technical Public Documentation
Docs? Tons. Specs? Buried in numbers like 802.11a/b/g/n/ac/ax/be and counting.
Full spec: IEEE 802.11 Specs
GitHub repo: https://github.com/esp8266/Arduino (because someone had to make it work on a toaster)
Reading the spec requires coffee, courage, and a tolerance for acronyms.
Overview
Wi-Fi talks to laptops, phones, printers, lightbulbs, and your cousin’s “smart” doorbell. It’s fast (sometimes), reliable (rarely), and power-hungry (always). Great for high-data stuff. Terrible for sleeping nodes. But if you need TCP/IP now, it’s already in the room.
Architecture
Basic Service Set (BSS) – access point as the boss, clients as obedient (or not) devices. Extended Service Set (ESS) for roaming and frustration. Mesh exists, but barely anyone uses it. Cloud-managed? Of course. Offline fallback? If you're lucky.
Device Roles
Access Point (AP): the overlord. Station (STA): the gadget. Repeater: the lag machine. Controller: the guy behind the curtain. Everyone screams packets at everyone else and pretends it’s fine.
Channelization
2.4 GHz – crowded like a mall on Black Friday. 5 GHz – faster, shorter range, still gets stomped by walls. 6 GHz (Wi-Fi 6E) – sounds cool, still rare. Channels overlap. Interference is tradition. DFS channels? Good luck.
Frames
So many frame types. Management, control, data. Headers that change per standard. Payloads wrapped in layers. CRCs at the bottom if someone remembered. Frame size? 2304 bytes plus overhead, if the stars align.
Networking
Full IP stack. IPv4 and IPv6. DHCP, DNS, NAT – the whole circus. Peer-to-peer? Possible with Wi-Fi Direct, if the devices agree. Otherwise, everything routes through the AP – the one device guaranteed to be overwhelmed.
Security
WEP (bad), WPA (meh), WPA2 (standard), WPA3 (hope). Uses AES, PSK, 802.1X – depending on how paranoid you are. Open networks? Might as well just shout your password out loud.
Networking Process
Scan. Probe. Auth. Assoc. DHCP. Ping. Drop. Retry. It’s like dating, but with less honesty. Roaming? Mostly broken. Fast transitions? Only if the firmware didn’t ship last year.
Use Cases
Laptops, phones, cameras, smart TVs, printers, thermostats, and all the IoT devices you wish weren’t on Wi-Fi. Works well if you have power and bandwidth to burn. Not for deep sleep, low-power, ultra-reliable needs. Unless you're feeling reckless.