Protecting the Grid against MAD Attacks

Power grids have recently been shown to be vulnerable to MAnipulation of Demand (MAD) attacks using high-wattage IoT devices. In this paper, we introduce two forms of defenses against line failures caused by these attacks: 1) we develop two algorithms named SAFE and IMMUNE for finding efficient operating points for generators during the normal operation of the grid such that no lines are overloaded instantly after any potential MAD attacks, and 2) assuming lines can temporarily tolerate overloads, we develop efficient methods to verify in advance if such overloads can quickly be cleared by changing the operating points of the generators after any attacks. We then define the novel notion of α D-robustness for a grid indicating that line overloads can either be prevented or cleared after any attacks based on the two forms of introduced defenses if an adversary can increase/decrease the demands by at most α fraction. We demonstrate that practical upper and lower bounds on the maximum α for which a grid is α D-robust can be found efficiently in polynomial time. Finally, we evaluate the performance of the developed algorithms and methods on realistic power grid test cases.