Not sure what you are referring to? TP-Link Deco devices do not "phone home" to any Internet based servers. The only problem is that most routers need to have Internet connectivity so that they can perform DNS resolution. Without an Internet connection the routers fail and then stop functioning properly.

So if you are trying to create an isolated or siloed network, without an Internet connection then, I believe that you may want to investigate using a 169.254. 0.0 - 169.254. 255.255 network for your home siloed network. That network is non-routable. But I don't know if that can be configure that in a Deco. You probably need a Network expert to respond.

  @DAServices My question is regarding to being able to configure the device. My understanding is that most settings can only be changed via the app, which requires one to log in with their TP-Link account. I want to make sure that if I have no internet (both on my mobile device running the app and from the Deco) that I can continue to configure the Deco devices. Another similar case would be if TP-Link's servers were to go down.

  @staticcaster Deco's have a built-in web server that you can access via a browser. You'll need to figure out the IP address the device is using. Not sure what the default username and password is if yu have not set it up yet, but I'm sure it's an internet search away.