John Case wrote:
Recent events related to "big content" pursuing individual file sharers based on ISP logs are _very interesting_.
My first thought is that this usage is tracked via filename - you are guilty until proven otherwise if bittorrent traffic indicates a filename that matches [Hh][Uu][Rr][Tt].[Ll][Oo][Cc][Kk][Ee][Rr].
Its complex. the surprising and short answer is - bit torrent traffic does not have *any* file names; the torrent descriptor file contains the file layout, individual file hashes, and an overall hash that is used to reference the torrent in communications (in fact, no torrent client will talk to you unless you reference a file hash it is currently holding "live", either for download or seeding). Alternative distributed peer locating systems and "trackerless" cloud torrents have a secondary system for handling this information, but move the actual data using the torrent protocols. You also get "private" trackers, who require a unique registered token per registered user before they will share peer information. Most of these prohibit alternative peer finding mechanisms, which is good, but conversely also track which torrents users have uploaded and how much (in bytes) which, given those logs are kept, is potentially a goldmine for anyone wishing to link interest in a given file to a list of people who have "distributed" it in part or whole.