Abstract: In order to evaluate network security state in real time and make up for the shortcomings of low accuracy and poor practicability of traditional network node intrusion risk assessment method,a new network node intrusion risk assessment method based on fuzzy game rules was proposed.A set of finite state sets is used to describe the network,and the benefit matrix and fuzzy game elements are given to obtain the expected income of intruders and network nodes.On this basis,the fuzzy game rules are given.The risk assessment model is constructed according to the assets,threats,weaknesses and risk factors through the fuzzy game rules.After the quantification of the strategy cost and income,the fuzzy game tree of the network node is established,and the nash equilibrium is obtained.Combined with the income function of intruders and network nodes,the expectation of network nodes’ risk under fuzzy game rules is obtained,and the value of network node’s intrusion risk is determined.The threshold value is used to judge whether alarm is needed to prevent the network node from being invaded.Experimental results show that the proposed method has high accuracy,reliability and practicability.

Key words: Evaluation, Fuzzy game rule, Intrusion, Network node, Risk