Leader-follower hierachical decision model for critical infrastructure protection and its solving algorithm.

To meet the need of optimal fortification planning for critical infrastructure, a supply system was regarded as a network composed of service facilities, demand nodes and linking arcs. The authors utilized the theory of leader-follower hierarchical decision to describe the interrelationship between the defender and the attacker. When modeling the problem, the impact of capacity limitation of facilities was taken into consideration, and a "protection-interdiction-reassignment'' tri-level hierarchical decision model was then proposed. Based on a "greater demands prior-closest assignment" heuristic strategy, the model was simplified and solved through a binary tree search procedure. Experiments show that the heuristic can always get good approximations of optimal ones. The solutions to this model can help effectively alleviate the reduction of system efficiency, even avoid deadly system impairment if the protection investment is sufficient. [ABSTRACT FROM AUTHOR]