rwbradley wrote:
Maybe some clarification is in order from the OP. Are you referring to message such as a cease and desist email message with threats of legal action from a Lawyer via your Internet provider, an email asking you to click on a link, or a popup message on the desktop of your computer. The first would indicate a WiFi security issue, the second would indicate a spam email, and the third would indicate some form of malware on one of the computers.
And some clarification about Bittorrent. The transfer of Bittorrent packets technically speaking can be highly secure but usually only when using private trackers. Any torrent for a movie, game, TV show etc. will never have a private tracker if you got it from a public source like PirateBay. There are also still a lot of Bittorrent clients out there that do not even have encryption turned on or only on when an peer has it enabled too. Further even when fully encrypted, Trackers know everything being downloaded and uploaded. They monitor the status of all torrents by collecting info like what IP has what pieces a torrent (peer) and what IP has the full file (seed) and are able to tell your client how many seeds and peers are currently active and which ones you can connect to for which pieces. This is usually how the MPAA and RIAA find out you have downloaded the most recent song or movie. They become a tracker, and as soon as you load the torrent, you load their tracker along with all the "legit" trackers, and then they are able to monitor your torrent session by "tracking" your download/upload status. This also means any peer who is also downloading the file can track the status of any other peer. If this was an official cease and desist letter from a lawyer, you can bet they DO know exactly what, when and where was downloaded.
Could be a scam, but depends on where the notice came from? If its legit from your service provider, or a law firm representing a studio, though I would research this further even if its a legit firm, but running a borderline extortion scam itself, then you need to locate and plug the source of this exploit.
You don't want to be one of the examples that some studios have made, such as 25,000 lawsuits served to alleged Bittorent down-loaders of The Hurt Locker movie. Or 23,000 for The Expendables. Yet, in your case, the forensics wouldn't trace back to any of your systems. Just to your IP address. But can be a time consuming if not a costly hassle nonetheless.
In any case, a good explanation by
rwbradley. Though, admittedly, don't follow the specifics for tracking suspected piracy, I'm technically still an employee for one of the industry organizations mentioned that actively does.