Requirements for the gateway node hardware:
Run from wall power
Persistent state
Discover network link to the Internet
Internet connectivity via WiFi or cellular (through external modules if needed)
Receive system configuration data from the Internet and self configure (zero touch from fresh powerup)
I/O sufficient to allow for double duty as a data collection node
Linux
OS to allow flexibility in feature set
Local storage sufficient to buffer data collection in the event of link outages