CAN-bus was chosen as the control network for its robustness, ample network length at considerable speed (e.g. 125 kbit/s at 500 m), modules can communicate with each other without a master, availability of components. VSCP was chosen as the protocol because it is open and simple.

At the lowest level 1-Wire devices make the cheapest way for remote input and output (e.g. temperature sensors, switches,...) to the CAN nodes. A RF gateway will be used to control not connected appliances, e.g. a radiator valve.

The Linksys WRT54G router can be hacked to provide a serial connection to the control network, allowing remote control over WIFI and the internet. The voip software also runs on the router. Note that for the default operation, there is no PC running and thus enabling the energy saving goal.