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Peer-to-Peer Traffic Advisory Service FAQ

The Information Security Office sends email advisories to users whose network usage profile indicates high-volume peer-to-peer traffic, and who are therefore more likely to be the target of a DMCA (Digital Millennium Copyright Act) complaint or lawsuit.

Frequently Asked Questions


I've read the email, but why are you really doing this?

There are two basic reasons why we provide this service: (1) we want to, and (2) we have to.

We want to.

  • We want to prevent Stanford network users from losing network privileges or from getting sued. Many people who get DMCA complaints didn't realize they were sharing files until the copyright holders found them. Since we don't go out looking for copyright-protected material, we have no surefire way to warn people before they get in trouble.

    There are legitimate purposes for peer-to-peer file sharing, and we want to make sure our file-sharing users are doing so knowingly and lawfully. The traffic advisory message is our way of giving a harmless heads-up to inform people about file-sharing. Another reason we are sending out this message is because file-sharing takes up a lot of bandwidth.  Since we often hear that people didn’t even know they had active file-sharing clients running, we hope that through this message we may re-capture bandwidth when unintentional file-sharing clients are disabled.

We have to.

  • We have to comply with federal laws and regulations. One of our obligations under these regulations is to combat copyright abuse with "technology-based deterrents." We've chosen to implement this notification service rather than the more onerous measures that some other universities employ, such as charging users for Internet use by the gigabyte or banning peer-to-peer traffic entirely.


Why did I get this message? Am I in trouble?

If you received a traffic advisory message, it's because the network traffic patterns from your computer suggested that it may be generating a high volume of peer-to-peer file sharing traffic. You are not in any trouble (at least not because you received this message). In fact, we presume that you are complying with copyright laws and University policies.  The notice is provided only as a service to those people who are unknowingly file sharing. If you know you're only sharing files with the legitimate permission of the copyright holder, you can ignore the message.


How do you decide who to send notices to?

Network traffic gets roughly classified by the kinds of connections being made and ranked by the number of different computers the connections are made to. Machines that are in approximately the top 0.1% of that ranking are flagged for notification, and messages are sent to the corresponding computer owners or administrators.


Are these messages targeted at students?

No. The notifications are triggered entirely by the shape of traffic coming from a particular machine. Both the residential network and the main campus network are included. Students, staff, and faculty are all possible recipients.


Can you tell me what file I was transferring, and when?

No, we can't. The traffic classifier does not look at the content of your network traffic, so we have no idea what you're transmitting.

Even if you tell us when you received a notice, we still can't tie that to a precise day or time when the traffic was seen because the accounting is cumulative over the sample period and the messages are randomly delayed before they are sent out.


I don't think I'm transferring any files. What should I do?

Some programs use peer-to-peer file sharing protocols in ways that are not obvious to the user. The traffic classifier doesn't know anything about the nature of the program — it just reacts to the use of these protocols. Check to see if you are using any of the following:

  • Skype
  • Skype transmits phone calls over the Internet using software based on the KaZaa file-sharing protocol.
  • World of Warcraft
  • World of Warcraft uses the BitTorrent protocol to distribute software patches, which are sometimes large enough to hit the PacketShaper's radar.
  • Abacast
  • Abacast is an audio/video streaming client for accessing online radio, TV, and webcams. Their streams are distributed through a hybrid peer-to-peer protocol.

Other possible ways that a person's computer unexpectedly ends up generating  file-sharing traffic are:

  • another person in that person's office or household installed file-sharing software without their knowledge; or
  • that person's computer has been broken into.

Unfortunately, these reasons may not give you much protection in responding to complaints or lawsuits from a copyright holder.

You can get help securing your computer from the Information Security website, from your local computer support person, submitting a Help request, or by phoning 5-HELP (650-725-4357).

There are also self-help tools on the Essential Stanford Software website.

Last modified March 24, 2017