Research On End-to-End QoS Based On BACnet/IP

BACnet is a data-communication protocol which is dedicated to the field of building automation field.Its goal is to integrate products with different manufacturers, different functions in one system and achieve the interoperability of equipment manufacturers.BACnet/IP is a BACnet standard based on IP technology.The application of this standard makes remote control of intelligent building possible. BACnet/IP is different from the tunneling technology,it can directly support IP-based protocol BACnet equipment,can be effective in the conduct of BACnet broadcasting on IP networks,and can increase or decrease BACnet equipment in arbitrary position.With the enlargement scale of network,diversification of applications and service requirements of increasement on the network quality,the simple and do-best mode of transmission has been unable to meet the requirements.The real-time network transmission decreased significantly when network load increases.However,in the current BACnet/IP standard,there is not special regulation on network service quality requirement.Therefore,a suitable subject about BACnet/IP network service quality management system has been raised,which is based on the analysis and research of the BACnet/IP protocol as well as mainstream QoS technology.The system includes the following elements:application layer adaptive mechanism,priority management mechanism,queue management and congestion control mechanism and the solution of multicast.Among them,in the part of queue management for BACnet/IP network,a new queue management and congestion control algorithm has been raised.Thesis designed a series end-to-end QoS Strategy of BACnet/IP.Its main work as follows:(1)Introduction of the BACnet study background,research situation domestically and overseas.Meanwhile,introduced innovation and studying contents.(2)Introduction of related technologies,including BACnet protocol,as well as the mainstream of lP-based network QoS technologies.(3)The implement of the BACnet/IP end-to-end QoS overall design.On this basis,with illustration to give a detailed account of BACnet/IP network service quality management framework of the overall design.(4)Elaborated various strategy of BACnet/IP end-to-end service quality management,including:application layer adaptive mechanism,priority management mechanism,queue management and congestion control mechanism and the solution omulticast.The paper made expansion on NS₂ simulation tools,at the same time, added the BACnet/IP module through simulation results to illustrate the adaptive methods.(5)Elaborated a new algorithm called DDQ,which is a BACnet/IP network design queue scheduling and congestion control algorithm.At the same time,evaluated the performance of DDQ algorithm by using NS₂.