When hosting a local network game, the other user randomly gets disconnected from the network.  On my instance of Minecraft, the screen flickers and the Mojang symbol partially shows but enlarges before returning to normal. Then a red bar appears at the bottom of the screen which disappears after a moment.

The other user is unable to reconnect from their instance even if I am still logged in.  The only way to reconnect is for me to reset my instance by closing and reopening Minecraft on my PC. then reentering the world.