Wikipedia
LonTalk
LonTalk is a protocol optimized for control. Originally developed by Echelon Corporation for networking devices over media such as twisted pair, powerlines, fiber optics, and RF. It is popular for the automation of various functions in industrial control, home automation, transportation, and buildings systems such as lighting and HVAC; see Intelligent building, the protocol has now been adopted as an open international control networking standard in the ISO/IEC 14908 family of standards. Published through ISO/IEC JTC 1/SC 6, this standard specifies a multi-purpose control network protocol stack optimized for smart grid, smart building, and smart city applications..