A Game Theoretic Method to Model and Evaluate Attack-Defense Strategy in Cloud Computing

Cloud computing has attracted much interest recently from both industry and academic. However, it is difficult to construct perfectly secure mechanisms, in face of complex and various attack behaviors in cloud computing. In this paper, a stochastic game model (SGM) is proposed to describe the attack-defense behavior in cloud computing, the physical machine, attack-defense behavior and their attributes are modeled by using SGM, thus forming the attack-defense game model of cloud computing. On this basis, the Nash equilibrium of attack-defense process of physical machine is computed in order to get the best defense strategy. The related theories of Petri net are used to verify the correctness of proposed method. The computation formula and the actual meaning of performance index are given. The enforcement algorithm is also proposed. Both case study and simulation results show that the proposed method can adapt quickly to the changes in cloud application, thus improving the security of cloud computing.