Comparing multilateral and bilateral exchange models for content distribution

Users of peer-to-peer systems are often incentivized to contribute their upload capacity in a bilateral manner: downloading is possible in return for uploading to the same peer (e.g., BitTorrent). An alternative is to use multilateral exchange to match user demand for content to available supply at other peers in the system. Multilateral exchange can be enabled through prices and a virtual currency. Monetary incentives have been previously proposed to incentivize uploading in P2P systems. We provide a formal comparison of P2P system designs based on bilateral exchange with those that enable multilateral exchange via a price-based market mechanism to match supply and demand.