Design and Implementation of Fault Tolerance in the BACnet/IP Protocol

Digital communication networks have become a core technology in advanced building automation systems. The building automation and control network (BACnet) is a standard data communication protocol designed specifically for building automation and control systems. BACnet provides the BACnet/IP (B/IP) protocol for data communication through the Internet. Every B/IP device uses a B/IP broadcast management device (BBMD) to deliver remote or global BACnet broadcast messages. In this paper, we propose a fault-tolerant BBMD for the B/IP protocol. The fault-tolerant BBMD improves the connectivity of B/IP networks because a backup BBMD automatically inherits the role of a defective primary BBMD. The fault-tolerant BBMD was designed to provide backward compatibility with existing B/IP devices. In this paper, we implemented the fault-tolerant BBMD and examined its validity using an experimental model.