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Windows Vista DRM: World's Longest Suicide Note?

by The DVD Insider January 03, 2007
Microsoft Windows Vista Logo

Microsoft Windows Vista Logo

The Vista Content Protection specification could very well constitute the longest suicide note in history.

Vista's content protection mechanism only allows protected content to be sent over interfaces that also have content- protection facilities built in. Currently the most common high- end audio output interface is S/PDIF (Sony/Philips Digital Interface Format). Most newer audio cards, for example, feature TOSlink digital optical output for high-quality sound reproduction, and even the latest crop of motherboards with integrated audio provide at least coax (and often optical) digital output. Since S/PDIF doesn't provide any content protection, Vista requires that it be disabled when playing protected content. In other words if you've invested a pile of money into a high-end audio setup fed from a digital output, you won't be able to use it with protected content. Similarly, component (YPbPr) video will be disabled by Vista's content protection, so the same applies to a high-end video setup fed from component video.

Alongside the all-or-nothing approach of disabling output, Vista requires that any interface that provides high-quality output degrade the signal quality that passes through it. This is done through a "constrictor" that downgrades the signal to a much lower-quality one, then up-scales it again back to the original spec, but with a significant loss in quality. So if you're using an expensive new LCD display fed from a high-quality DVI signal on your video card and there's protected content present, the picture you're going to see will be, as the spec puts it, "slightly fuzzy", a bit like a 10-year-old CRT monitor that you picked up for $2 at a yard sale [Note C].

Note C includes:
"In order for content to be displayed to users, it has to be copied numerous times... Windows Vista's content protection (and DRM in general) assume that all of this copying can occur without any copying actually occurring, since the whole intent of DRM is to prevent copying... So in order for Windows Vista's content protection to work, it has to be able to violate the laws of physics and create numerous copies that are simultaneously not copies."

In fact the spec specifically still allows for old VGA analog outputs, but even that's only because disallowing them would upset too many existing owners of analog monitors. In the future even analog VGA output will probably have to be disabled. The only thing that seems to be explicitly allowed is the extremely low-quality TV-out, provided that Macrovision is applied to it.

The same deliberate degrading of playback quality applies to audio, with the audio being downgraded to sound (from the spec) "fuzzy with less detail" [Note D].

Amusingly, the Vista content protection docs say that it'll be left to graphics chip manufacturers to differentiate their product based on (deliberately degraded) video quality. This seems a bit like breaking the legs of Olympic athletes and then rating them based on how fast they can hobble on crutches.

In July 2006, Cory Doctorow published an analysis of the anti- competitive nature of Apple's iTunes copy-restriction system ("Apple's Copy Protection Isn't Just Bad For Consumers, It's Bad For Business", Cory Doctorow, Information Week, 31 July 2006). The only reason I can imagine why Microsoft would put its programmers, device vendors, third-party developers, and ultimately its customers, through this much pain is because once this copy protection is entrenched, Microsoft will completely own the distribution channel. In the same way that Apple has managed to acquire a monopolistic lock-in on their music distribution channel (an example being the Motorola ROKR fiasco, which was so crippled by Apple-imposed restrictions that it was dead the moment it appeared), so Microsoft will totally control the premium- content distribution channel. Not only will they be able to lock out any competitors, but because they will then represent the only available distribution channel they'll be able to dictate terms back to the content providers whose needs they are nominally serving in the same way that Apple has already dictated terms back to the music industry: Play by Apple's rules, or we won't carry your content. The result will be a technologically enforced monopoly that makes their current de-facto Windows monopoly seem like a velvet glove in comparison.

Here's an offer to Microsoft: If we, the consumers, promise to never, ever, ever buy a single HD-DVD or Blu-Ray disc containing any precious premium content [Note K], will you in exchange withhold this poison from the computer industry? Please?