Critical Infrastructure Protection and Resilience—Integrating Interdependencies

Throughout the world, there is strong recognition that critical infrastructure security and resilience need to be improved. Enhancing the protection and resilience of critical infrastructure has emerged as an urgent goal—a goal made more challenging by the complexity of these systems and their inherent interdependencies. Consideration of critical infrastructure interdependencies, as well as their integration into risk management and business continuity processes, is an important element of U.S Presidential Policy Directive 21 on Critical Infrastructure Security and Resilience (PPD–21), the Canada-United States Action Plan for Critical Infrastructure, and the European Program for Critical Infrastructure Protection. Several international standards also require the consideration of interdependencies between organizations and the effect on their risk management and business continuity practices. All of these documents, from the strategic level through the operational standards, involve the consideration of interdependencies that can exist among infrastructure, how they are managed, and how they affect business continuity, security, and resilience management. A “system of systems” approach can help establish the appropriate scope of an interdependency analysis, as well as the specific assets and/or subsystems for which resilience-related information should be collected.