Congestion control and the P2P value chain Damon Wischik, UCL Moez Draief, Imperial

P2P mechanism P2P algorithms typically choose peers at random They use congestion control, which means they download at a higher speed when the link is uncongested

Problems with P2P it doesn’t make sense to assign bandwidth based only on congestion low-bandwidth peer who has no content peer who can best disseminate the content peer with a good but pricey connection ? ? ? $$ it doesn’t make sense to pick peers at random

Research question How should capacity be apportioned between users? How should costs be split? What is the economy of P2P distribution?

The virtual economy of the Internet TCP, the Internet’s algorithm for congestion control, was invented by Van Jacobson in 1988, to save the Internet from congestion collapse In 2000, Frank Kelly proved that the TCP algorithm behaves as if there is a virtual economy

The virtual economy of P2P What “social welfare” do existing P2P algorithms seek to maximize? What is the economic interpretation of P2P tradeoffs? should I send to a content-poor peer, or to a well-connected peer? should I offer to upload, or should I pay to download? How does the economic interpretation translate into actual algorithms? How should ISPs use “price signals” in this “virtual economy” to control their networks? Will the network operate autonomically?