| abstract |
Low-cost intelligent control and communication devices (21, 22, 23, 51, 52) are arranged to communicate with one another over one or more shared physical media (10, 11), such as a powerline or a radio frequency band. No network controller is needed, because any device can act as a master, slave or repeater. Adding more devices makes the system more robust, by virtue of a simple protocol (30, 50, 60) for communication retransmissions and retries. |