BACnet (Building Automation and Control networks) is a data-communication protocol specifically designed for building automation applications.
1987 the ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) founded the committee 135 to create an open and neutral communication protocol for building automation. First published in 1995 the BACnet standard is under continuous maintenance by SSPC 135. A public review process before the formal approval assures acceptance by the industry or interested parties.
While starting as a national American standard BACnet has become a world-wide standard and was accepted by ISO as the standards ISO 16484-5 and ISO 16484-6.
The general architecture of BACnet describes three main parts, the BACnet data link layers, the BACnet objects and the BACnet application services.