Impact of the Computer System User When Creating Cyber Defense Strategies

Petri nets with Players, Strategies, and Costs (PNPSC) is an extension of Petri nets that can model cyberattacks and defenses. Previous work has created PNPSC nets for cyberattack patterns based on the MITRE Common Attack Pattern Enumeration and Classification (CAPEC) database. The previous PNPSC nets modeled two players, the attacker and defender, but did not account for the computer system user. This research enhances previously developed PNPSC nets by adding representation for the computer system user. The research also builds on previous work in which cyber defense strategies were generated and improved with an epsilon-greedy reinforcement learning algorithm. The results show that including a representation for computer system users impacts the strategies developed by the defender, who must now balance computer system usability with computer system security.