A recent white paper (2MB Word file) from Microsoft details the planned “output content protection” in the upcoming Windows Vista (previously known as Longhorn) operating system product. It’s a remarkable document, illustrating the real costs of Hollywood’s quest to redesign the PC’s video hardware and software.
The document reveals that movie studios will have explicit veto power over what is included in some parts of Vista. For example, pages 22-24 describe the “High Bandwidth Cipher” which will be used to encrypt video data is it passes across the PC’s internal PCIe bus. Hollywood will allow the use of the AES cipher, but many PCs won’t be able to run AES fast enough, leading to stutter in the video. People are free to design their own ciphers, but they must go through an approval process before being included in Windows Vista. The second criterion for acceptance is this:
Content industry acceptance
The evidence must be presented to Hollywood and other content owners, and they must agree that it provides the required level of security. Written proof from at least three of the major Hollywood studios is required.
The document also describes how rational designs are made more expensive and complicated, or ruled out entirely, by the “robustness” rules Hollywood is demanding. Here’s an example, from page 27:
Given the data throughput possible with PCIe, there is a new class of discrete graphics cards that, to reduce costs, do not have much memory on the board. They use system memory accessed over the PCIe bus.
In the limit, this lack of local memory means that, for example, to decode, de-interlace, and render a frame of HD may require that an HD frame be sent backward and forward over the PCIe bus many times – it could be as many as 10 times.
The frames of premium content are required to be [encrypted] as they pass over the PCIe bus to system memory, and decrypted when they safely return to the graphics chip. It is the responsibility of the graphics chip to perform the encryption and decryption.
Depending on the hardware implementation, the on-chip cipher engine [which wouldn't be necessary absent the "robustness" requirements] might, or might not, go fast enough to encrypt the 3 GByte/sec (in each direction) memory data bandwidth.
These are just a few examples from a document that describes one compromise after another, in which performance, cost, and flexibility are sacrificed in a futile effort to prevent video content from leaking to the darknet. And the cost is high. As just one example, nearly all of us will have to discard our PC’s monitors and buy new ones to take advantage of new features that Microsoft could provide – more easily and at lower cost – on our existing monitors, if Hollywood would only allow it.
There can be little doubt that Microsoft is doing this because Hollywood demands it; and there won’t be much doubt among independent security experts that none of these compromises will make a dent in the availability of infringing video online. Law-abiding people will be paying more for PCs, and doing less with them, because of the Hollywood-decreed micromanagement of graphics system design.