Digital Identity

Trusted Computing Platforms

If you were applying a little creative thinking during the preceding discussion of the DRM reference architecture, you probably thought of several ways that the scheme could be defeated. That issue is the chief weakness of DRM. As we've seen, for the user to view or otherwise use the content, it has to be rendered in a usable format, and that allows ample opportunity for the content to be redirected to a use that wasn't specifically authorized.

The iTunes example illustrates some of the problems :

• Once an audio file has been put on a CD, it can be ripped in another format, such as MP3, without any DRM, because the DRM wrapper can't be transferred to the CD.

• Remote rights administration, needed for customer service, opens up further opportunities for people to exploit the system and get around DRM.

• The Fairplay system has been cracked, and methods for playing Fairplay-protected files outside of iTunes have been published on the Internet.

• Even if all of these problems were solved, the analog feed going to the speakers could always be redirected to a recording device, and the audio file could be re-encoded in another format.

These examples show just how hard it is to really protect content in a digital format. In addition to the tradeoffs made by Apple that were examined in the case study, Apple is inconveniencing their legitimate users while still allowing the rights of copyright holders to be undermined by determined crackers.

These problems have led to numerous ...