Incentives and Resource Sharing in Spectrum Commons

It has been suggested that light regulation in the form of etiquette protocols, device design and bargaining amongst users will suffice to mitigate a tragedy of the commons in unlicensed spectrum. In this paper we propose a game theoretic model to examine this claim. In this game, each user decides whether or not to set up an access point, which operates on a particular (single) band. The effect of regulation is modeled in reduced form through transfers. A user who sets up an access point, provides payments to each neighbor who does not and suffers a disutility depending on the number of interfering access points. A user who does not set up an access point, receives payments from each neighbor that does. For a suitable model of payoffs, the game is a potential game and best response updates converge to a Nash equilibrium of the game. For any interference parameters, there is a suitable transfer resulting in a Nash equilibrium which is efficient. However, all Nash equilibria may not be efficient.