Tri-level optimization of critical infrastructure resilience

Abstract

We introduce a new way to perform network analysis on critical infrastructure that is superior to Risk Analysis and Management for Critical Asset Protection (RAMCAP), currently used by the Department of Homeland Security. We introduce the idea of a Design-Attack-Defend (DAD) model that determines the optimal defense plan for a critical infrastructure network within a specified budget constraint. Design-Attack-Defend first determines worst-case attacks and then determines where to defend or build additional infrastructure that will maximize the surviving efficiency of the infrastructure after a malicious attack or natural disaster. Design- Attack-Defend ensures that the defense plan suggested is optimal to a range of attacks, out of all possible defense plans, within budget constraints. The Design-Attack-Defend will always give a solution at least as good as RAMCAP and as a simpler, bi-level Attacker-Defender model-and in many cases it can be expected to suggest a better plan for where to defend or build additional critical infrastructure. We demonstrate with a model of the Western U.S. railroad network.