Saw yet another comment on a blog about Vista and DRM, and thought I could contribute a few distinctions:
DRM Supporting Features
This refers to a set of technologies that help enable practical DRM, but aren’t DRM themselves. This includes stuff like APIs that tell applications that if the output path for audio or video enables perfect digital quality capture without protection. It also includes technologies like “Protected Processes”. Most DRM Enforcing features have hacky ways to do this stuff which can lower system reliability or performance, so adding it as a OS feature improves system reliability and performance in the presence of such applications. These features also tend to overlap with other aspects of security, such a trusted OS private data store or generic encryption decryption libraries. This is the “DRM” support that Vista included in Windows.
DRM Enforcing Features
This refers to applications and shared libraries that allow DRM’d media to play. Typically this handles media decryption and uses various DRM Related Features to help enforce the DRM policy. ITunes, Quicktime, Windows Media Player, Zune and IRM are examples of this type of category. In this category DRM is a capability not a requirement.
DRM Limited Features
This refers to a product or feature that requires DRM and only DRM. The IPhone Apps, most of the iTMS, and the Zune Pass are all examples of this. The hallmark of this notion is that some key device usage is conditional on DRM enforcement.
I’m okay with DRM Supporting and DRM Enforcing, and have a personal policy with regards to DRM Limited Features. Basically it’s a personal acknowledgement that you can’t own DRM’d stuff.; you can only rent it. If you understand this, then you can enjoy features like netflix streaming, the Zune Pass or other time fee based services. The furthest I’ve crossed this line is “buying” Xbox360’s arcade games. Anyhow, when people bitch about Vista and DRM, I’d love to hear reasons why DRM Supporting Features are a bad thing, and specifically how Vista’s actual implementation of them have been problematic.