Valuation of information and the associated overpayment problem in peer-to-peer systems

Most incentive schemes for peer-to-peer (P2P) file-sharing are rate-based, only giving consideration to upload rate when measuring contributions. Besides giving room for strategic peers to benefit from concealing high value chunks, rate-based metrics also aggravate overpayment. Overpayment is a phenomenon that one pays a higher than necessary price for goods. In a P2P system, overpayment exists because in most cases, the incentive schemes have design flaws. Specifically, in rate-based systems, bandwidth allocation policies ignore different values of different chunks, and it directly induces overpayment. In this work, taking the chunk value in the reciprocity process into consideration, the overpayment problem in a BitTorrent network is investigated, and four side effects of overpayment are identified. A novel strategy called value-based BitTorrent (VBT) is proposed, which is found to be able to alleviate the degree of overpayment and consequently relieve the side effects of overpayment.