I'm using a Deco M4 in Access Point mode. Under Advanced Settings, I can enable an IoT Network. If this feature only worked in Router mode, I would expect it not to be visible, just like the other router-specific settings that are hidden in Access Point mode.

However, I'm not sure whether the IoT Network is actually working as intended. My impression is that the two networks are not truly separated. The reason is that the Deco M4 is connected to my Ziggo ISP router. In the router's interface, all devices appear together in a single list. Because of this, I get the impression that devices on the IoT network could still access the main network through the router.

My understanding is that devices on the IoT network should not be able to communicate with devices on the main network. Can anyone explain whether the IoT Network feature actually works when the Deco M4 is operating in Access Point mode?

I'm using it for my smart home devices, so proper network separation is important to me.