Peer-assisted content distribution matches user demand for content
with available supply at other peers in the network. Inspired by this
supply-and-demand interpretation of the nature of content sharing, we
employ price theory to study peer-assisted content distribution. In
this approach, the market-clearing prices are those which exactly
align supply and demand, and the system is studied through the
characterization of price equilibria.

In this talk, we rigorously analyze the efficiency and robustness of
price-based multilateral exchange.  We compare and contrast
multilateral content exchange with bilateral exchanges such as
BitTorrent.  Bilateral barter-based systems such as BitTorrent have
been attractive in large part because of their simplicity; however,
little attention has been devoted to studying whether efficiency and
robustness has been lost in return for this simplicity. Our research
takes a step towards filling this gap.