  This paper proposes a new event-based parameter switching method for the
control tasks of cybersecurity in the context of preventive and reactive cyber
defense dynamics. Our parameter switching method helps avoid excessive control
costs as well as guarantees the dynamics to converge as our desired speed.
Meanwhile, it can be proved that this approach is Zeno-free. A new estimation
method with adaptive time windows is used to bridge the gap between the
probability state and the sampling state. With the new estimation method,
several practical experiments are given afterwards.
