Optimizing active cyber defense

Abstract. Active cyber defense is one important defensive method for combating cyber attacks. Unlike traditional defensive methods such as firewall-based filtering and anti-malware tools, active cyber defense is based on spreading “white ” or “benign ” worms to combat against the attackers ’ malwares (i.e., malicious worms) that also spread over the network. In this paper, we initiate the study of optimal active cyber defense in the setting of strategic attackers and/or strategic defenders. Specifically, we investigate infinite-time horizon optimal control and fast optimal control for strategic defenders (who want to minimize their cost) against non-strategic attackers (who do not consider the issue of cost). We also investigate the Nash equilibria for strategic defenders and attack-ers. We discuss the cyber security meanings/implications of the theoretic results. Our study brings interesting open problems for future research