There is disclosed an anti-intrusion method for a communication network comprising a plurality of network elements. The method comprising the following steps: a) providing a passive monitoring component, a decision making component, and an action making component cooperating with the communication network; b) at the passive monitoring component, detecting management information indicative of an attack against at least one network element, processing the management information thus generating infection data and transmitting the infection data to the decision making component; c) at the decision making component, receiving the infection data, making a decision about an action to be carried out to block the attack, and transmitting the decision to the action making component; and d) at the action making component, based on the decision, instructing the at least one network element to perform the action.