Node Capture Games: A Game Theoretic Approach to Modeling and Mitigating Node Capture Attacks

Abstract

Unattended wireless sensor networks are susceptible to node capture attacks, where the adversary physically compromises a node, creates functional copies (clones) of it and deploys such clones back into the network, in order to impact the network’s functionality. In the absence of a centralized authority, distributed clone detection methods have been developed to mitigate this attack. In this paper, we show that the node capture attack and the network response can be modeled as a simultaneous, noncooperative, two-player game. In developing the game-theoretic framework, we consider a deterministic, linear dynamical model of the attack, as well as a general, stochastic model. For the deterministic model, we develop three games, all of which have quadratic utility for the valid network, whereas the adversary’s utility depends on the assumptions about ist abilities. For the stochastic model, we develop a game with convex utility functions. For each game, we prove the existence of a pure strategy Nash Equilibrium and present an efficient way of solving the game. These equilibria can then be used in choosing the appropriate parameters for detecting and responding to the attack. Simulations are provided to illustrate our approach.