Author: Ed Felten

  • Record Companies Boxed In By Their Own Rhetoric

    Reports are popping up all over that the major record companies are cautiously gearing up to sell music in MP3 format, without any DRM (anti-copying) technology. This was the buzz at the recent Midem conference, according to a New York Times story. The record industry has worked for years to frame the DRM issue, with…

  • Wikipedia Leads; Will Search Engines NoFollow?

    Wikipedia has announced that all of its outgoing hyperlinks will now include the rel=”nofollow” attribute, which instructs search engines to disregard the links. Search engines infer a page’s importance by seeing who links to it – pages that get many links, especially from important sites, are deemed important and are ranked highly in search results.…

  • AACS: Modeling the Battle

    [Posts in this series: 1, 2, 3, 4, 5, 6, 7.] By this point in our series on AACS (the encryption scheme used in HD-DVD and Blu-ray) it should be clear that AACS creates a nontrivial strategic game between the AACS central authority (representing the movie studios) and the attackers who want to defeat AACS.…

  • AACS: Sequence Keys and Tracing

    [Posts in this series: 1, 2, 3, 4, 5, 6, 7.] This is the sixth post in our series on AACS, the encryption scheme used for HD-DVD and Blu-Ray discs. It’s time to introduce another part of AACS: the Sequence Key mechanism. Throughout our AACS discussion, we have done our best to simplify things so…

  • AACS: Title Keys Start Leaking

    [Posts in this series: 1, 2, 3, 4, 5, 6, 7.] Last week we predicted that people would start extracting the title key (the cryptographic key needed to decrypt the contents of a particular next-gen DVD disc) from HD-DVD discs. Indeed, it turns out that WinDVD, a popular software player that runs on PCs, leaves…

  • AACS: Extracting and Using Keys

    [Posts in this series: 1, 2, 3, 4, 5, 6, 7.] Let’s continue our discussion of AACS (the encryption scheme used on HD-DVD and Blu-Ray discs) and how it is starting to break down. In Monday’s post I gave some background on AACS and the newly released BackupHDDVD tool. Recall that AACS decryption goes in…

  • AACS Decryption Code Released

    [Posts in this series: 1, 2, 3, 4, 5, 6, 7.] Decryption software for AACS, the scheme used to encrypt content on both next-gen DVD systems (HD-DVD and Blu-ray), was released recently by an anonymous programmer called Muslix. His software, called BackupHDDVD, is now available online. As shipped, it can decrypt HD-DVDs (according to its…

  • 2007 Predictions

    This year, Alex Halderman, Scott Karlin and I put our heads together to come up with a single list of predictions. Each prediction is supported by at least two of us, except the predictions that turn out to be wrong, which must have slipped in by mistake. Our predictions for 2007: (1) DRM technology will…

  • 2006 Predictions Scorecard

    As usual, we’ll start the new year by reviewing the predictions we made for the previous year. After our surprisingly accurate 2005 predictions, we decided to take more risks having more 2006 predictions, and making them more specific. The results, as we’ll see, were … predictable. Here now, our 2006 predictions, in italics, with hindsight…

  • Holiday Stories

    It’s time for our holiday hiatus. See you back here in the new year. As a small holiday gift, we’re pleased to offer updated versions of some classic Christmas stories. How the Grinch Pwned Christmas: The Grinch, determined to stop Christmas, hacks into Amazon’s servers and cancels all deliveries to Who-ville. The Whos celebrate anyway,…