Analyzing cross-sector interdependencies

This paper discusses cross-sector infrastructure interdependencies and key risk considerations, analysis approaches, research and development needs, and the range of interdisciplinary skills required for comprehensive cross-sector analysis. Traditional analysis of interdependencies involves characterization of infrastructure-to-infrastructure linkages to identify the key infrastructure components that, if lost or degraded, could adversely affect the performance of other infrastructures. Such analysis is motivated by the recognition that a series of incidents could interact (cascade) across critical infrastructures to degrade the service upon which all depend. From a risk perspective, cross-sector analysis also must involve identifying and characterizing a wide range of threats (natural and accidental, systems related, and intentional), vulnerabilities (physical and cyber), and consequences of loss (e.g., health and safety, economic, national security, environmental, socio-political). Such information provides a foundation for making defensible, cost-effective infrastructure protection and operation decisions to ensure the security and reliability of our interdependent systems.