Each time a new digital rights management (DRM) system is released, hackers are not far behind in cracking it. Reverse engineers have taken down the security protecting content encoded for Windows Media, iTunes, DVDs, and HD-DVDs. SecurityFocus contributor Federico Biancuzzi tracked down Nate Lawson, the co-designer of the Blu-ray content protection system, and discusses the challenges of defending digital content, including the basic principles and mistakes of the design process, how much the hardware can help, the link between software protection and software security, and the role of security through obscurity.