We just got a Chromecast so my wife can watch Netflix kind of decently (we'd watch it through Kodi and libinputstream, but the UI is still quite different to the Netflix one which is more intuitive). The Chromecast being Google stuff, I'd like to shield it from the rest of the network. It really only needs a way to the internet (it's an Ultra, which has a network jack in the power adapter, so it's wired into the network), and a way to talk to the smartphone(s) for casting. It has no other business on the network.
What's the most elegant way to shield the LAN from the Chromecast? I was thinking a separate VLAN, but the smartphones are still in the LAN network, so then I guess I'd need to filter on IP. What's the best way to go about this?