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RF Torrent: A Peer to Peer Live Distribution Algorithm

S. Nagarajan, G. Amudha


Peer-to-peer file-sharing applications suffer from a fundamental problem of unfairness. Free-riders cause slower download times for others by contributing little or no upload bandwidth while consuming much download bandwidth. Previous attempts to address this fair bandwidth allocation problem suffer from slow peer discovery, inaccurate predictions of neighboring peers bandwidth allocations, underutilization of bandwidth, and complex parameter tuning. We present RF Torrent, a new deficit-based distributed algorithm that accurately rewards peers in accordance with their contribution. A RF Torrent peer simply uploads the next data block to a peer to whom it owes the most data as measured by a deficit counter. RF Torrent is resilient to exploitation by free-riders and strategic peers, is simple to implement, requires no bandwidth over allocation, no prediction of peers rates, no centralized control, and no parameter tuning.


RF Torrent, Peer to Peer File Sharing, Quality of Service, Free Riders

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