Spectrum Sharing as Congestion Games

A fundamental problem in wireless networking is efficient spectrum sharing. In this paper, the authors study this problem in the context of decentralized multi-user frequency adaptation, with the objective of designing protocols that are efficient, agile, robust, and incentive-compatible. Their approach is based on the theory of congestion games, a class of games that models the competition for resources among multiple selfish players. In a congestion game, when a player unilaterally switches her strategy, the change in her own payoff is the same as the change in a global objective known as the potential function. Hence any sequence of unilateral improvements results in a pure strategy Nash equilibrium.