Motivated by the problem of optimal security resource deployment in critical infrastructure systems, we study a non-zero-sum security game over the substations of a power system in which the player payoffs depend upon the maturity of the security resources at each substation according to NERCCIP standards. Extending previous work, we give a structural characterization of the possible types of Nash equilibria in our non-zero-sum additive security game model, present feasibility conditions for equilibria of each type, and propose a novel algorithm to compute an equilibrium. Utilizing our characterization of the possible equilibria in additive security games, we propose a method to obtain a suboptimal solution to the problem of maximizing the expected outcome to the system operator by varying the maturity of security resources deployed at each substation and demonstrate the method by simulation.
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On the Characterization of Saddle Point Equilibrium for Security Games with Additive Utility
In this work, we investigate a security game between an attacker and a defender, originally proposed in [6]. As is well known, the combinatorial nature of security games leads to a large cost matrix. Therefore, computing the value and optimal strategy for the players becomes computationally expensive. In this work, we analyze a special class
of zero-sum games in which the payoff matrix has a special structure which results from the additive property of the utility function. Based on variational principles, we present structural properties of optimal attacker as well as defender’s strategy. We propose a linear-time algorithm to compute the value based on the structural properties, which is an improvement from our previous result in [6], especially in the context of large-scale zero-sum games.
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- Award ID(s):
- 1739969
- PAR ID:
- 10311933
- Date Published:
- Journal Name:
- GameSec Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1007/978-3-030-64793-3_19
