Will one of my fellow networking nerds please confirm as to whether or not TP-Link routers will continue to route local traffic between physically and wirelessly connected devices when a modem is not connected to any possible WAN port?  I know that the Deco mesh units require a modem to be connected (regardless of internet status), and this has caused me a great deal of inconvenience, as my modem reboots every 15 minutes without an internet connection.  So every 15 minutes I lose connection to my physically connected devices, and it pretty much renders my home network useless.

I tried asking TP-Link customer service about their routers, but they're telling me that their routers require a connection to the Internet to function, let alone just being connected to a modem.  This would make their routers worse off than their Deco units!!  So yeah, I don't believe them; I don't think they even understand that computers can talk to each other without internet.  That would not be a good router (not even sure you could call it a router at that point), but after dealing with their Deco units, I wan't to be 100% sure.

I know who can be sure!  You guys!  :D

Thank you in advance!

I_R_Dippy