智能变电站中的组播泛洪抑制技术

Multicast Flooding Suppression Technology in Smart Substation

在智能变电站的过程层中存在大量的组播泛洪数据,对网络的实时性及可靠性造成了严重影响。为解决上述问题,通过以太网的交换原理引入二层组播在以太网络中的转发过程,深刻剖析组播泛洪的原因。结合智能变电站中的应用场景及部分实验数据,深入分析802.1Q VLAN隔离广播域的原理及在变电站中抑制组播泛洪的设置方法及实验效果,介绍设置静态组播来静态改变组播介质访问控制(media access control,MAC)地址表的机制;并给出详细的实施方案,GARP组播注册协议(GARP multicast registration protocol,GMRP)通过协议数据的交互来动态改变以太网交换机上组播地址表信息,以实现控制组播报文转发范围。并根据工程实际应用现状,从调试运维便捷性及智能设备可靠性等方面对比3种方法的特点,并给出建议的技术路线。

The existence of a large number of multicast flooding data in the process level of smart substation has a serious impact on the real-time performance and reliability of network. In order to solve the above problem,through the exchange principle of Ethernet, the forwarding process of second-layer multicast in Ethernet is expounded, and the causes of multicast flooding is deeply analyzed. Combined with the application scenario in smart substation and some experimental data, the in-depth analysis of the principle of the 802.1Q VLAN isolating broadcast domain and the setting method of multicast flooding suppression in substation and the experimental results are introduced. And the mechanism of setting static multicast to change the static media access control（MAC） address table and the detailed implementation plan of the program are described. The fact that the GARP multicast registration protocol（GMRP） can change the information of multicast MAC address table on Ethernet switch through the interactive protocol data to control the forwarding range of multicast packet is depicted. And based on the practical engineering application, three kinds of methods are compared from the aspects of debugging operation and maintenance convenience and reliability of intelligent equipment, then the recommended technology route is given.