Abstract:

Nowadays,most studies of risk assessment methods based on game theory use complete information game model.These models cannot deal with the situation in which the attacker and the defender do not know each other’s actions.In this paper we establish an attackdefense model based on static Bayesian game theory to categorize the attacker and the defender into different types.Then,we analyze the Bayesian equilibrium of the game comprehensively,and improve the taxonomy and cost quantitative method of the classical strategies with consideration of the strike back acts of the defender and the success rate of attacks.Under the premise that the actions of the attacker are predicted based on game equilibrium,we use the risk calculating algorithm to calculate the risk in the information system. Simulation results  prove the effectiveness of the proposed model and the algorithm.

Key words: risk assessment;static Bayesian game;cost quantitative method;mixed strategy;Bayesian equilibrium