- From: Jeff Jaffe <jeff@w3.org>
- Date: Wed, 24 Apr 2013 07:33:09 -0400
- To: Henri Sivonen <hsivonen@iki.fi>
- CC: Dominique Hazael-Massieux <dom@w3.org>, public-restrictedmedia@w3.org
On 4/24/2013 2:35 AM, Henri Sivonen wrote: > On Tue, Apr 23, 2013 at 5:25 PM, Jeff Jaffe <jeff@w3.org> wrote: >> First, I would make clear that I don't believe that content owners are even >> close to giving up on DRM. > OK. Targeting content to user-modifiable CDMs would amount to giving > up on DRM, so we should equally believe not to be even close to > user-modifiable CDMs. > >> DRM opponents have told me that DRM doesn't work. They assert that every >> DRM system built has been broken and presumably every such system will be >> broken. >> >> Based on that, why do content owners continue to advocate DRM? I can only >> guess. But I imagine that the combination of social contract and difficulty >> in avoiding the installed DRM system is what they are relying on. > Systems that treat end-users as untrusted are terrible for > establishing social contracts. I think the ability to invoke > anti-circumvention law even over broken DRM is the more likely > explanation. Consider HDCP. Even though the keys were leaked, the > threat that HDCP might still constitute an "effective technical > protection measure" gives Hollywood control over what features > law-abiding consumer electronics makers can put in mass-market > devices. > >> DReaM is not an example of (as you call it), "giving up on DRM". > I didn't suggest it was. Sorry for the misunderstanding. In the thread we were talking about DReaM. I said that content owners might be willing to compromise to accept DReaM type systems. You said that compromise would mean giving up on DRM. That was why I thought you said that DReaM would mean giving up on DRM. > I said user-modifiable (as in user-buildable > as opposed to the user having to send modifications to someone else > for building) DRM amounts to giving up on DRM. DReaM was a system with > disclosed source code (except for private keys). AFAICT, it wasn't a > system where end-users could build the client-side implementation of > DRM from source *and have it work* (in the sense of being able to use > it to render the same movies as with a build made by someone else). > >> So while DReaM would be easier to break than DRM, it shares some of the >> advantages (to content owners) as real DRM. > Why do you categorize DReaM as something other than "real DRM"? > >> I pointed out (on April 12th) in response to Dom that DReaM exists. > DReaM doesn't exist anymore. It's a dead project. AFAICT, the major > Hollywood studios never made a substantial portfolio of movies > available using DReaM. Therefore, DReaM doesn't really prove anything > of relevance. I think you are missing the context of the April 12th response. Dom had asked whether there was an open source compatible DRM solution. I said "DReaM appears to indicate feasibility." > > However, even if one assumes that DReaM would have been acceptable to > major Hollywood majors, DReaM would still only be proof that a DRM > scheme can be "open source" in the sense that the source code except > keys is disclosed. It wouldn't be proof of being Open Source in the > sense of downstream recipients of the source code enjoying the > freedoms typically associated with Open Source. > >> You pointed out (on April 22nd) that there are flaws in this. > More to the point, I pointed out that "open source" in the sense of > "disclosed source code except keys" is not particularly interesting > and the more interesting questions are whether everyone downstream > gets to build a fully-functioning CDM and whether downstream gets to > do so on an RF basis--i.e. whether the downstream freedoms associated > with Open Source are actually there. DReaM seems to have been in the > "disclosed source code except keys" category. > >> I pointed out that there are answers to these flaws. > I don't think you addressed my point about the flaw in the framing of > the question or my point about Open Source not only about being about > disclosed source but also about the recipients of the source code > actually having the freedoms necessary build and distribute > interoperable products using the source code. Correct. I did not address this point. Actually, to be precise, I conceded that DReaM (to my understanding) is probably NOT compatible with GPLv3. Dom, in framing this as a question about open source compatible DRM was anchoring the discussion on a long-established W3C practice to make sure that our standards are implementable in open source. I was merely pointing out that this would be possible with DReaM. To your point, W3C could certainly add a new practice to make sure that our standards are compatible with the "no 'disclosed source code except keys'" category. In that case DReaM like solutions would indeed be excluded. > >>> If a DRM scheme is incompatible with GPLv3, it's a pretty strong hint >>> that it's incompatible with some important things typically associated >>> with Open Source other than mere source disclosure, such as >>> royalty-freeness and the disclosed source actually being useful to a >>> downstream recipient. >> I'm not sure I understand this argument. Are you saying that DReaM is >> incompatible with other open source licenses as well? > GPLv3 is the license that most strongly protects the ability of > downsteam licensees to exercise all the relevant software freedoms > associated with Open Source or Free Software. If a technical scheme is > not compatible with GPLv3, it's a strong hint that there's a catch > somewhere that denies relevant freedoms to downstream recipients even > if the source code has been disclosed. The disclosure of source code > can be rendered useless to would-be downstream users of the source > code if using or distributing a product built from the source is > encumbered by patents or if the origin of executable builds of the > source is required to be cryptographically certified such that > interoperability can be denied to executable builds depending on who > made them. > > -- > Henri Sivonen > hsivonen@iki.fi > http://hsivonen.iki.fi/ >
Received on Wednesday, 24 April 2013 11:33:12 UTC