> if my compuer and IoT hub is on my main network, and the lightbulb is on the guest one, how do they talk? If your IoT devices aren't on the same subnet as yo

> if my compuer and IoT hub is on my main network, and the lightbulb is on the guest one, how do they talk? If your IoT devices aren't on the same subnet as your smartphone or computer, the vast majority of their "frontend apps" are already DOA. If you're lucky, those apps might let you explicitly specify the device's IP address (in a half-baked fashion that still doesn't work very well).