Can smart-home devices communicate across a guest network?
Guest networks commonly isolate clients from the main LAN and sometimes from each other, which can stop discovery/control. Use a designed IoT network if local communication is required.
SSID/VLAN; client isolation; controller location; mDNS.
Network engineering.
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On a managed Wi-Fi plan
Apply supported segmentation policy; do not weaken all isolation for one device.
On another provider's router
ISP guest behaviour varies.
What to be careful of
Safeguarding/business policies require owner approval.
Where this comes from: Official · see the original source ↗ · Draft—technical review · checked 17 August 2026