Floodgate: A Micropayment Incentivized P2P Content Delivery Network

As the sale of digital content is moving more and more online, the content providers are beginning to realize that bandwidth infrastructures are not easily scalable. The emergence of peer-to-peer content delivery networks present these providers with a way to overcome this limitation. However, such networks have so far been ad-hoc in nature. One of the main reason for this has been the lack of incentives for end users to contribute their bandwidth to the network. In this paper we present the design and implementation of a peer-to-peer protocol named Floodgate that provides a micropayment based incentive for peers to contribute their bandwidth. Floodgate implements an optimistic fair exchange protocol and is designed to be resilient against targeted attacks. Performance measurements, including those conducted over the PlanetLab infrastructure, show that Floodgate´s security and cryptographic overheads are low when compared against the standard BitTorrent implementation.