KNX (standard)
KNX is a standardized (EN 50090, ISO/IEC 14543), OSI-based network communications protocol for intelligent buildings. KNX is the successor to, and convergence of, three previous standards: the European Home Systems Protocol (EHS), BâtiBUS, and the European Installation Bus (EIB or Instabus). The KNX standard is administered by the KNX Association.
Read more about KNX (standard): KNX Protocol, Wire Transmission, Configuration Modes, KNX Products, List of KNX Open Source or Free Software