This paper proposed an immune based novel model for intrusion prevention for dynamic change of real network.It presented the formal definition and mathematical description of the model and its detection performance.Based on dynamic self-sets,it designed the mathematical model and equations of dynamic tolerance and dynamic Ab.The experimental data included the data collected from the actual LANs and KDDCup1999 intrusion detection evaluation data sets.The experimental results prove that the model has higher detection rate and lowe...