Reading Between the Lines: Lessons from the SDMI Challenge

The Secure Digital Music Initiative is a consortium of parties interested in preventing piracy of digital music, and to this end they are developing architectures for content protection on untrusted platforms. SDMI recently held a challenge to test the strength of four watermarking technologies, and two other security technologies. No documentation explained the implementations of the technologies, and neither watermark embedding nor detecting software was directly accessible to challenge participants. We nevertheless accepted the challenge, and explored the inner workings of the technologies. We report on our results here.