| 摘要 |
<p>When a traffic storm has occurred in an open flow network, a frame of a cause is dropped in a flow unit without carrying out the indiscriminate drop of the frame and the down of the port. Specifically, a controller detects increase of the traffic in a short time from the statistic data regularly acquired from each of the switches under the control of it. The controller starts a storm detection mode upon the detection. In the storm detection mode, packets are extracted randomly from the switch for a predetermined time period, as a sample packet. The controller determines which of a broadcast storm, a multicast storm and a unicast storms has occurred, based on the sample packets. The controller determines that the traffic storm has occurred, when any of them has occurred. When the traffic storm has occurred, the controller sets an entry defining a rule (match condition) showing the packet which is a cause of the storm and an action in which it is written that the packet is dropped, to a port of the switch based on data of the analyzed sample packets by using a "FlowMod" message.</p> |
