关键词: 蠕虫传播, 信任模型, 信任度, 传播概率

Abstract: The evaluation mechanism based on the trust degree of network nodes is an effective method to prevent worm propagation. Aiming at the problem that the existing node trust degree calculation model is insensitive to worm attack behavior and not comprehensive to the identification of malicious nodes, this paper proposes a trust update model that considers the risk of worm propagation. Through the definition of the STIDR state in the worm propagation model, the relationship between node trust degree and propagation probability is quantitatively characterized. And a trust update model is established under three conditions of direct risk, indirect risk and propagative risk. The simulation results show that compared with the basic trust model, the trust update model considering the risk of worm propagation in this paper makes the trust degree of infected state nodes lower, the number of infected state nodes less, and the number of isolated state nodes more, which indicates the update of the trust degree makes the identification of the infected state node more effective. To a certain extent, the purpose of resisting worm attacks and inhibiting worms from spreading in the network is achieved.

Key words: worm propagation;trust model, trust degree, propagation probability