February 2, 2014
t The blackout of August 14, 2003, showed that electric power grids are vulnerable to cascading failure. Since then, numerous methods of vulnerability analysis have been developed to help the owners and operators of power networks and other infrastructure systems protect them against possible catastrophic events (including attacks by intelligent adversaries). With cascading failures, even small attacks can have a large impact. Cascading failures have historically been considered a major unsolved problem for complex networks such as electricity systems, but recent developments in probabilistic analysis of cascading failure are making it possible to take cascading failures into account in methods of vulnerability assessment. In particular, our game-theoretic model can be used to analyze how an intelligent adversary might seek to take advantage of a network’s vulnerability to cascading failure. Specifically, our model provides a tool to simulate power flows within the network, and analyze how attackers can use their knowledge of cascading failure. Our model can also be used to compare the effectiveness of different types of investments to make systems more resilient, including both hardening components and also making the system less vulnerable to cascading failure (e.g., by increasing the capacities of transmission lines, or adding new lines).