Decision Support for Protection of Interdependent Critical Infrastructure Systems

Zhang Yunwei

Abstract

Critical infrastructure systems have become the fundamental pillars of modern society. The services they deliver have penetrated into every aspect of daily life that disruption of any of them would cause significant inconvenience and could even make the society paralyzed. Due to the crucial roles they play, protection of these systems against all possible disruptions which include natural disasters, artificial attacks and random failures has been of interest to researchers for decades. Especially after the 911 terrorists’ attack on World Trade Centre, there emerges rising need of defending critical infrastructures. More effort has since been devoted to this specific field.

In recognition of this need, this thesis focuses on strategy making in defending the critical infrastructure systems against terrorists’ attack. In it, a system approach has been developed to provide a defender a means to allocate his resources so that the impact of the attack in the worst case scenario is minimized. The first phase of the approach is to understand the adversary’s attacking strategy. Models are established to obtain a strategy which accommodates the adversary’s two major objectives of maximizing the damage and minimizing the resource wastage. In light of the way the adversary makes his strategy in a given situation, the second phase gives support to the defender in allocating resources to protect the infrastructure systems. All the models in the approach are developed by integrating network flow problems and deterministic network interdiction problems. A case study will be provided to illustrate the models in each phase.