Patent ID: 8732832

Claim:
A routing apparatus comprising: a reception unit configured to receive a packet transmitted in a network; a transmission unit configured to transmit the packet along a transmission path; a memory unit configured to store data and/or information required for an operation and to store a plurality of threshold values for respective multiple different types of server state information of one or more servers, wherein the types of server state information include at least two of a CPU load of the server, a connection request standby amount of a backlog queue of the server, or a memory utilization rate of the server; and a controller configured to set the transmission path of the packet in the network and perform packet switching along the transmission path, wherein the reception unit receives server state information from servers at every certain time, the memory unit stores the received server state information, and the controller calculates a change in the state of the servers based on comparing multiple values of the received server state information with at least a portion of the plurality of threshold values, and determines that a server is attacked when the change in the multiple values of the received server state information is greater than corresponding ones of the threshold values.