COMMUNICATION SYSTEM AND DDOS ATTACK COOPERATION COUNTERMEASURE METHOD

摘要

To provide a DDoS attack cooperation countermeasure technology which can simultaneously realize avoidance of congestion of inter-AS link band and leveling of resource utilization ratio of mitigator of each AS.SOLUTION: A communication system having a plurality of autonomous systems (AS), the AS has a cooperation countermeasure device which cooperates with other ASs for DDoS attack detected in a target AS. The cooperation countermeasure device includes a congestion inspecting portion for inspecting the congestion state of a link through which the communication between the cooperating ASs passes and when the cooperating upstream AS and the downstream AS are not directly connected to each other, the congestion inspecting portion of the upstream AS inspects the congestion state of the link through which communication between the cooperating upstream AS and downstream AS passes. When congestion has occurred in the link, the cooperation countermeasure device of the upstream AS continues to increase the coping volume until the congestion is resolved, and the cooperation countermeasure device of the downstream AS adjusts the coping volume on the basis of the coping volume when the congestion is resolved.SELECTED DRAWING: Figure 3