The idea for this little project was to keep the Guest Wi-Fi secure but still practical for visitors at home.

When people come over to visit and ask for the Wi-Fi password, it's good practise to offer them internet access via a sepearte guest vlan.

Not everyone can be trusted these days, so I rotate random generated passwords each day for the guest Wi-Fi.

To avoid typing random characters, a qr-code is displayed via a cheap and tiny LCD-screen and automatically connects you to the guest Wi-Fi when scanned with your phone.

A cron script on Openwrt changes the guest Wi-Fi password every night with a random generated 12 character string. A QR-code is generated on the Luci login page and a simple text file is placed in the www folder with the QR-code payload. The ESP8266 (NodeMCU) together with a ST7789 LCD-screen refreshes the payload over the main Wi-Fi and the display generates a QR-code which a phone can scan.