Poster: Destabilizing BitTorrent's clusters to attack high bandwidth leechers

BitTorrent protocol incentivizes sharing through its choking algorithm. BitTorrent choking algorithm creates clusters of leechers with similar upload capacity to achieve higher overall transfer rates. We show that a malicious peer can exploit BitTorrent's choking algorithm to reduce the upload utilization of high bandwidth leechers. We use a testbed comprising of 24 nodes to provide experimental evidence of a distributed attack in which the malicious peers increase the download time for high bandwidth leechers by up to 16% and increases average download time of the swarm by up to 15% by using distributed and loosely-coupled malicious peers which comprise only 4.7% of the swarm. The countermeasures of this attack are a part of our ongoing research work.