- From: Charles Pritchard <chuck@jumis.com>
- Date: Wed, 07 Mar 2012 01:12:04 -0800
- To: Henri Sivonen <hsivonen@iki.fi>
- CC: Mark Watson <watsonm@netflix.com>, "<public-html@w3.org>" <public-html@w3.org>
On 3/7/12 12:31 AM, Henri Sivonen wrote: > On Mon, Mar 5, 2012 at 7:55 PM, Mark Watson<watsonm@netflix.com> wrote: >> > >> > On Mar 5, 2012, at 3:52 AM, Henri Sivonen wrote: >> > >>> >> On Sat, Mar 3, 2012 at 4:19 AM, Mark Watson<watsonm@netflix.com> wrote: >>>> >>> On Mar 2, 2012, at 1:22 AM, Henri Sivonen wrote: >>> >> >>> >> You said in another email that it's a requirement that mp4 files be >>> >> encrypted using ISO Common Encryption. That seems to mean AES-CTR >>> >> inside the container. So the message that ultimately needs to be >>> >> transferred is the AES-CTR key. It seems to me it would be possible to >>> >> define one message format for transferring the AES-CTR key to the CDM >>> >> and have the protection systems adapt to consume this one HTML media >>> >> key messaging format. I don't see why a priori HTML would need to >>> >> adapt to multiple back ends that implement ISO Common Encryption >>> >> instead of the back ends adapting to a standard message format. >> > >> > I think the reason is IPR. Yes, one could easily define such a message format that sends the key in such a way that only the CDM can see it. IANAL, but I'm told that you would then be in an IPR minefield. > It's troubling to see spec proposals go into the mode of declaring > defeat in face of patents from the get-go without even trying to > develop an RF solution under the W3C PP. > Well, here's a recent post I saw from the internet, for a first crack at some hardware based key jangling: http://blog.habets.pp.se/2012/02/TPM-backed-SSL Not as impressive as the on-chip work of some of the new "HD"-capable devices that run it all on hardware. -Charles
Received on Wednesday, 7 March 2012 09:12:29 UTC