Dynamic Network Security Analysis Based on Bayesian Attack Graphs

Abstract

In order to overcome the difficulties that current attack graph model cannot reflect real-time network attack events,a method is proposed including a forward risk probability update algorithm and a forward-backward combined risk probability update algorithm,which meets the needs of real-time analyzing network security.It first performs specific quantitative analysis on the uncertainty of each node in the graph,and uses Bayesian networks to calculate their static probabilities.After that,it updates the dynamic probability of each node along the forward and backward paths according to the real-time network security events,instantly reflecting the changes of external conditions and assessing real-time risk levels across the network.Experimental results show that the method can calibrate and adjust the risk probability of each node according to the actual situation,which helps the network operator correctly understand the dangerous levels of the network and make better decision for defense and prevention of the next attack.

Keywords

• bayesian network|attack graph|real time|static probability|dynamic probability|risk probability