针对传统以太网采用带有冲突检测的载波侦听多路访问(CSMA/CD)的媒质访问协议给工业控制带来实时性差的弱点,分析了全双工交换式以太网应用于楼宇自控系统的可行性,并对其进行了介绍,分析了其优点。在以太网一网到底结构的楼宇自控系统中采用全双工交换式以太网,对典型的二级交换网络结构进行了实时性计算,结果表明采用这样的以太网通信方式能保证楼宇自控系统中的实时性要求。 Aiming at the shortcoming of poor real-time performance of industrial control using media access protocol with collision detection Carrier Sense Multiple Access (CSMA / CD) in traditional Ethernet, this paper analyzes the application of full-duplex switched Ethernet in building automation system Feasibility, introduced and analyzed its advantages. The structure of the Ethernet network in the end of the building automatic control system using full-duplex switched Ethernet, the typical two-stage switching network structure was calculated in real time, the results show that the use of such Ethernet communication can guarantee building automation system Real-time requirements.