Risk assessment of cyber attacks in ECPS based on attack tree and AHP

Abstract

In order to assess the influence of cyber attacks on the overall system of electric cyber-physical system (ECPS), a quantitative risk assessment method based on attack tree and Analytic Hierarchy Process (AHP) is proposed. Attack tree is utilized to model the attacks in cyber space of ECPS. Attack attributes of leaf nodes, level of attacker, attack costs and possibility of being detected, are proposed and assigned to meet the characteristics of cyber attacks in ECPS. Then previous work about risk indexes is improved and AHP is explored to quantify the attack impacts on ECPS. Lastly, risk value of cyber attacks in ECPS is calculated with the presented quantitative equations. This method considers the impacts of cyber attacks on power system and combines the factors in the cyber space and physical space of ECPS. The case study indicates the proposed method is practical and reasonable. This work can be a reference for risk assessment in ECPS.