Content pricing in peer-to-peer networks

We provide a game theoretic model of content production and sharing in a peer-to-peer (P2P) network. We characterize two benchmark outcomes: Nash equilibrium (NE) without any incentive scheme and social optimum. We show that the P2P network is not utilized at an NE outcome, whereas social optimum in general requires the utilization of the P2P network. In order to obtain a socially optimal (SO) outcome among self-interested peers, we introduce a pricing scheme where downloading peers compensate uploading peers for content provision. For any SO outcome, we can find a pricing scheme with link-dependent linear prices that achieves the SO outcome as an NE. We illustrate our results with several examples. Our illustration shows that the structures of social optimum and optimal prices vary depending on the characteristics of peers such as cost parameters and connectivity.