| 摘要 |
A method for intercepting a DoS(Denial of Service) attack by using TCP(Transmission Control Protocol) state transition is provided to intercept the DoS attack previously by monitoring a flow of packets transmitted between a client and a server through the TCP, thereby effectively reducing loads of a server party and providing a safer service. If a server receives a connection request(SYN(Synchronous)) packet of a client, a TCP(Transmission Control Protocol) state of the server party is moved from a listen state to a connection request reception(SYN_RCVD) state. After the server transmits a connection request response(SYN/ACK(Acknowledge)_1) packet to the client, the TCP state of the server party is moved from the connection request reception state to a response wait(ACK_WAIT) state. If the server receives the same connection request again, the TCP state of the server party is moved from the response wait state to a closed state to safely terminate TCP connection. |
