Network users can choose among different security solutions to protect their data. Those solutions are offered by competing providers, with possibly different performance and price levels. In this paper, we model the interactions among users as a noncooperative game, with a negative externality coming from the fact that attackers target popular systems to maximize their expected gain. Using a nonatomic weighted congestion game model for user interactions, we prove the existence and uniqueness of a user equilibrium, and exhibit the tractability of its computation, as a solution of a convex problem. We also compute the corresponding Price of Anarchy, that is the loss of efficiency due to user selfishness, and investigate some consequences for the (higher-level) pricing game played by security providers.
['Patrick Maillé', 'Peter Reichl', 'Bruno Tuffin']
Interplay between security providers, consumers, and attackers: a weighted congestion game approach