Princeton computer science professor Edward Felten has posted several interesting thoughts regarding the ARDG press ban on his excellent weblog, Freedom To Tinker.
Some within ARDG have expressed the view that the ban on press attendance is necessary because many who attend ARDG meetings are not authorized to speak to the press on behalf of their companies. As a result, so the argument goes, many who would otherwise contribute to the ARDG discussions would be forced to remain silent if press were in the room.
The more you think about it, the less this looks like a valid argument and the more like circular reasoning. After all, any chill felt by attendees is occassioned by their companies' policies regarding the press. It seems that these policies need to be justified, rather than being relied upon to justify exclusion of the press.
But all of this may overstate the import of the issue. So, rather than questioning the company policies, I'd like to make a few observations regarding the context in which these concerns arise.
First, it has been my experience that the majority of engineers who attend CPTWG and BPDG meetings never say a word. To the extent this proves to be the case at ARDG, their employers need not worry about their remarks being attributed to the company.
Second, many who speak at these meetings are authorized by their companies to speak to the press. I have frequently seen Michael Epstein, Chris Cookson, Bob Schwartz, Brad Hunt, Jim Burger, Seth Greenstein, and others quoted in the press on topics relating to CPTWG issues. These fine gentlemen are expert at choosing their words with care and precision. Their employers and clients need not fear for their discretion should a few reporters appear at our meetings.
Third, to the extent some of the most important contributions come in the form of questions, it is not clear to me that companies need worry about a question to someone else being construed as a company position.
Fourth, it has always been my understanding that nothing said in these meetings is confidential, nor are attendees prohibited in any way from talking to press (or anyone else) about what transpires at the meetings. Accordingly, under our current rules, when someone contributes a bon mot to our meetings, that person's employer may see the substance of the remark in the next morning's press coverage.
On the other side of the coin, the recent experience with the BPDG suggests that excluding press makes it much more difficult for interested members of the public to evaluate the material that emerges from these groups. Despite the fact that the "broadcast flag" proposal, if adopted, would materially shape the future of DTV equipment in the U.S., I did not read any detailed analysis of its implications in Sound & Vision, The Perfect Vision, Stereophile Guide to Home Theater, Home Theater, or other consumer press. Hence, the consumers most likely to be affected by the proposal are hardly aware of it, much less able to adequately evaluate it. A similar outcome for the ARDG should be avoided.
So the question is whether the incremental burden imposed by admitting press is outweighed by the incremental benefit.
In a joint letter to the CPTWG co-chairs, the Electronic Frontier Foundation, Consumers Union, DigitalConsumer.org and Public Knowledge expressed concern regarding the exclusion of the press from ARDG meetings.
Citing its policy of excluding members of the press from its otherwise public meetings, CPTWG has extended this policy to include ARDG, which is a CPTWG subgroup. Drew Clark, of National Journal's Tech Daily, was ejected from ARDG when he attempted to attend its inaugural meeting.
Journalists serve a critical role in educating consumers, innovators, researchers and other interested members of the public about the debates taking place at ARDG. Recommendations that emerge from ARDG may become the basis for federal policy, as the final report of the BPDG became the basis for the "broadcast flag" proposal now being considered by the FCC. In the absence of press analysis, members of the public will be at a serious disadvantage in evaluating any policy proposals that may emerge from ARDG.
At the March 5 meeting of the ARDG, Brad Hunt from the MPAA offered a 3-slide presentation aimed at defining the "analog reconversion" problem and a "reference architecture" within which it might be examined. The presentation was not intended as a substantive proposal, but rather an overview of the scope of the problem.
Nevertheless, it introduced several themes that I expect will recur frequently during the ARDG's future meetings.
First, Brad introduced the MPAA's preferred rhetoric for the ARDG's efforts. The challenge is, in Brad's view, guaranteeing "equivalence" between protected digital outputs and analog outputs. At a minimum, I imagine this means that all analog links between digital video devices should offer roughly the same protections as the DTCP-protected FireWire links just now beginning to appear on high-def TVs and cable/satellite set-top boxes.
Of course, this is a bit like choosing the part of the playing field that is the most tilted in your favor, then arguing that all other parts of the field must be "leveled" up to match it.
Second, the PowerPoint slides foreshadowed what I predict will be two recurring battlefields at ARDG: "robustness" and "how many detectors".
It's all in Brad's last slide. The slide expressly recognizes the need for a "trusted environment" for both source and sink devices, by which Brad means to suggest that devices will have to be designed to be "robust" (i.e., with the hood welded shut to prevent user "tampering"). Just how "tamper-resistant" these devices have to be will be a major issue for makers of general purpose computers. It will also, of course, determine whether open source programmers have any ability to participate in the digital video revolution, as "robustness" rules disqualify open source programmers by charaterizing their products as "tamper-friendly" (i.e., user modifiable).
This slide also identifies a variety of places where watermark detection might take place in a sink device, without taking a position on where or how many times the device has to check for the watermark. This is also likely to be a major issue for IT companies (i.e., companies that produce devices intended for use with general purpose computers), whose enthusiasm for watermark detection may be inversely related to the number of places inside a general purpose computer that they have to install detectors.
The following ARDG meeting dates were set at the March 6 meeting:
The presentations made at the March 5, 2003 meeting of the ARDG are now posted on the ARDG website. Presentations from the second day (March 6) have not yet been posted.
On the first day, Jim Burger reviewed the history of the Data Hiding Study Group (DHSG), a group chartered back in 1997 to examine the state of the art in watermarking technologies. Jim is an attorney with the DC law firm of Dow, Lohnes and Albertson who represents the Computer Industry Group at ARDG. His presentation was a useful reminder that the "analog hole" is not a new problem, although its unfortunate moniker is of recent vintage. Although the DHSG issued an interim report in 1998, the task of selecting a watermarking technology was ultimately taken over by other entities and stalled amid inter-industry disagreement.
Adam Goldberg, from Sharp, offered a short presentation aimed at defining the scope of the ARDG's efforts.
Michael Epstein, from Philips, gave a very interesting presentation regarding a reference model that combined fragile watermarks with "play control". Content protection is accomplished by frustrating a user's efforts to display content that shows a "broken" watermark (for example, if it has been through a round of "lossy compression"). Broken watermarks could be detected by displays equipped with watermark detectors. This represents an interesting approach because it places less emphasis on preventing copying, focusing instead on reducing the value of unauthorized copies by making them unplayable on devices that include watermark detectors.
Brad Hunt, from the MPAA, gave a 3-slide presentation aimed at defining the analog reconversion problem and offering a "reference architecture" within which it might be addressed. More about the interesting questions raised by Brad's presentation in a later post.
Day Two (March 6) included presentations about two analog rights signaling systems that are already widely deployed: CGMS/A and Macrovision. Neither presentation has been posted yet.
CGMS/A is an analog "broadcast flag" meant to indicate the protected status of analog over-the-air broadcasts, as set out in the EIA/CEA 608-B standard. The flag is carried on line 21 in the "vertical blanking interval" (VBI) and is able to signal four possible states: no restriction; no more copies; one more generation; and no copies permitted. CGMS/A support is currently required by DVD-CCA license for some products, and is voluntarily supported in some DVD recorders and D-VHS recorders. Computer-based products have traditionally ignored CGMS/A flags, although Microsoft's new Media Center products offer limited CGMS/A support.
The Macrovision presentation outlined the protection systems most widely encountered on analog VHS recorders, known as Automatic Gain Control and Colorstripe Process. In addition to providing a mechanism for blocking analog VHS recording of protected content, these systems are also supported by certain digital devices, which detect the "trigger bits" associated with Macrovision protected content, and thus can operate to control redistribution in certain circumstances.
