A Wi-Fi QR code is essentially a piece of text encoding the Wi-Fi network’s security type, name (SSID), and password:
| Parameter | Example | Description |
|---|---|---|
| T | WPA | Authentication type; may be WEP, WPA, WPA2-EAP, or nopass (no password). If no password is required, this field may be omitted entirely. |
| S | mynetwork | The Wi-Fi SSID (network name). Required. If the SSID is an ASCII string that could be misinterpreted as hexadecimal (e.g., "ABCD"), it should be enclosed in double quotes. |
| P | mypass | The Wi-Fi password. Ignored if T=nopass (and may also be omitted). Double quotes are similarly recommended to prevent misinterpretation as hexadecimal. |
| H | true | Optional. Set to true if the SSID corresponds to a hidden network. Note: In versions prior to 4.7.8, this field was erroneously used to specify the phase 2 method. If this field is not a Boolean value, it will instead be interpreted as the phase 2 method (for backward compatibility with older versions). |
| E | TTLS | (WPA2-EAP only) EAP method, e.g., TTLS, PWD. |
| A | anon | (WPA2-EAP only) Anonymous identity. |
| I | myidentity | (WPA2-EAP only) Identity. |
| PH2 | MSCHAPV2 | (WPA2-EAP only) Phase 2 authentication method, e.g., MSCHAPV2. |
This format—called “Wi-Fi Network Config (Android)”—was proposed by ZXing. Any device supporting this encoding will display a prompt such as “Join Wi-Fi” upon scanning the QR code. Of course, successful connection requires that you are within the Wi-Fi network’s coverage area.
Just as typing www.xxx.com in Evernote automatically converts it into a clickable hyperlink, a Wi-Fi Network Config QR code is similarly parsed as a “hyperlink” that triggers joining a specific Wi-Fi network.
References
Share Wi-Fi Passwords More Elegantly—With Just One QR Code – Shaoshu Pai (Minority Report)