I'm beginning to consider some methods of enforcing security in this project. As far as control devices, that is anything that can issue commands to the system, I'll implement https and maybe some sort of password authentication. For the periphery devices, I'll put them on their own WiFi network so that they can be isolated from everything else. This way, I don't have to worry about encryption or authentication in addition to the WiFi security. I will implement some sort of extra security for the devices that control doors in the house. You can never have too much security for that which keeps your home safe.