| In this research, a security architecture based on the feedback control theory has been proposed. The first loop has been designed, developed and tested. The architecture proposes a feedback model with many controllers located at different stages of network. The controller at each stage gives feedback to the one at higher level and a decision about network security is taken.;The first loop implemented in this thesis detects one important anomaly of virus attack, rate of outgoing connection. Based on the feedback model, this symptom is fed back and a state model using queuing theory is developed to delay the connections and slow down the rate of outgoing connections. Upon implementation of this model, whenever an infected machine tries to make connections at a speed not considered safe, the controller kicks in and sends those connections to a delay queue.;PID controller is implemented to decide the number of connections going to safe or suspected queue.;The first loop implemented gives feedback to the architecture proposed about symptoms of an attack at the node level. (Abstract shortened by UMI.). |
