Method and system for preventing refusal service attack

The invention discloses a method and a system for preventing the attack of a denial service. The method includes the following steps: step A, before a connection request is processed normally, a message transmitted from an initiator to a target terminal is intercepted and captured and the message content of the message is analyzed; step B, the attack of the denial service is judged according to the message content and treatment for preventing the attack of the denial service is carried out. The invention can effectively prevent the attack of denial service in a normal working state.