Stable, distributed P2P protocols based on random peer sampling

In a peer-to-peer file sharing system based on random contacts where the upload capacity of the seed is small, a single chunk of the file may become rare, causing an accumulation of peers who lack the rare chunk. To prevent this from happening, we propose a protocol where each peer samples a small population of peers and makes an intelligent decision to pick which chunk to download based on this sample. We prove that the resulting system is stable under any arrival rate of peers even if the seed has small, bounded upload capacity.