Enabling per-device traffic analysis with separate VLANs, 802.1x MAC based authentication, and OpenWRT

Why For analysing what devices do on a network - specifically the shared medium of a wireless LAN - just packet tracing based on IP address is often not sufficient. There are multicasts, the initial DHCP requests, and potentially other types of traffic not captured by that. Even MAC address based packet tracing is problematic given recent defaults of MAC address randomization e.g. on Android (default since Android 10, optional before).