Which Wi-Fi technology do "Tuya" smart plugs use to get configured and join the Wi-Fi network?

Which Wi-Fi technology is being used in smart plugs like the ones from Chinese vendor "Tuya", where in order to register a new device to your Wi-Fi network through what's called quick connect mode, you just use your smartphone which is already in your Wi-Fi network and follow these steps:

  1. Power on the smart plug device.
  2. Through their app you select the wifi network name and enter the password.
  3. Then the app searches and connects directly to the device and registers it to your Wi-Fi network.

Note: I didn't press any WPS button, I didn't scan any QR codes, I didn't connect to the device's access point. I did nothing; I just told the app which Wi-Fi network.

What is this Wi-Fi technology, is it Wi-Fi Easy Connect or what?


Solution 1:

Data is encoded in the length of UDP broadcast packets. The length is visible (the same as unencrypyted packets). Source: https://www.elttam.com/blog/ez-mode-pairing/