How do I put smart devices such as Nest, Smart Lights etc on a different network?

Ricochet J · 3 Apr 2021 at 17:16

The advice I keep hearing is that smart devices such as Nest, Smart Lights, Alexa/Google hub etc need to be on a separate network.

I have a bog standard BT Router with one WiFi SSID. How do I put my smart devices on a separate network? Do they mean having 2 WiFi SSID's?

Also if Chromecast is on SSID1, and my phone is connected to SSID2, how will I be able to cast to Chromecast - don't they need to be connected to the same network SSIDs?

BigT · 3 Apr 2021 at 17:58

It’s not that easy if you want to do it properly.

I don’t know the BT router’s capabilities but the best way is to have a router that supports VLANs. You then put your IoT devices on a different VLAN to your ‘regular’ home network and create rules so that your ‘regular’ network can see your IoT network but not the other way around. The thing about that though is probably the rest of your network kit (access points, switches etc.) need to also support VLANs and lots of consumer orientated kit doesn’t.

Ricochet J · 4 Apr 2021 at 21:56

Thanks for responding - what you described sounds like a real PITA!

Is it worth it?

Hyburnate · 4 Apr 2021 at 22:01

Yeah without investment into new kit you won't be able to achieve what you want.

Your question surrounding SSIDs, this will not achieve any isolation, the reason being as you are just broadcasting names, they all lead back to the same physical network. Some routers these days support guest networks, these whilst lead back to the same network support user isolation, so whilst they're on your network per-say, they are blocked from being able to access any IP on your LAN, so if you are 192.168.1.X, then they can't access 192.168.0.1 - 192.168.0.253 (254 is your default gateway/dhcp server and .255 is reserved for network broadcasts).

Without getting technical, it's not likely going to be possible unless you connect all your smart devices to a Guest Wi-Fi, providing your router allows it, but then no device will be able to communicate with each other due to the way they work.