Users who participate in BitTorrent swarms for popular files are likely to have their IP addresses logged by monitoring companies within three hours. That's the conclusion of a paper being presented this week at the SecureComm conference in Italy by Tom Chothia and colleagues at the University of Birmingham.
Users who think they can evade detection just by using common blocklists are probably fooling themselves. "Publicly available blocklists, used by privacy-conscious BitTorrent users to prevent contact with monitors, contain large incidences of false positives and false negatives," the Birmingham team concludes.
source : http://www.cs.bham.ac.uk/~tpc/Papers/P2PSecComm2012.pdf; http://arstechnica.com/tech-policy/2012/09/trading-popular-files-on-bittorrent-youll-be-spotted-within-3-hours/