That's what I've been doing. For the local hardware, I use Arduino Nano clones, nRF24L01+ mesh networking chip, whatever sensors/actuators, and the MySensors

That's what I've been doing. For the local hardware, I use Arduino Nano clones, nRF24L01+ mesh networking chip, whatever sensors/actuators, and the MySensors library. Encryption and packet signing are both turned on. On the gateway, it is just a serial console opened up to a Arduino Nano and nRF24L01+. I use Node-Red on the machine the serial gateway is plugged into. I also use the MQTT broker Mosquitto as my backing store for IoT data, from any of my machines. I design my architecture around that. To connect between physical areas (from house to hackerspace), I use Tor Hidden Services, giving each endpoint a .onion address. With that, all my computers on the .Onion network can talk with each other as if they are on medium-high latency hub. And it also solves the problem of "staticIP/port forwarding/firewall rule change/dynDNS" crap. I drop Tor, set up a hidden service, route 22 to Tor, and off it goes. All I need do is keep track of that onion address. And that provides me devices I have complete control over, utilizing a cloud of computers I own. I'm looking in how I can blend in IPFS as well for logging capabilities.