Access Graph Based Risk Assessment Model for Network Information System

The risk assessment for network information system has experienced a stage from rule-based questionnaire investigation to model-based assessment. Many graph-based models have been proposed and applied to risk assessment. Attack Graph is widely used one. But attack graphs grow exponentially with the size of the network. In this paper, we propose a comprehensive framework for network vulnerabilities modeling and risk assessment by policy rules violations based on the access graph. As a complement to the attack graph approach, the access graph grows polynomially with the number of hosts and so has the benefit of scaling better to more practical, realistic size networks. This paper presents a novel risk assessment model for network information system based access graph. Compared with related works, our approach improves the performance and reduces the computational cost.