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Re: Encrypted Media proposal: Summary of the discussion so far

From: Charles Pritchard <chuck@jumis.com>
Date: Mon, 12 Mar 2012 12:24:26 -0700
Message-ID: <4F5E4D6A.9070107@jumis.com>
To: David Dorwin <ddorwin@google.com>
CC: Henri Sivonen <hsivonen@iki.fi>, public-html@w3.org
On 3/12/2012 12:08 PM, David Dorwin wrote:
>     For #2, what I'm asking is this: You will need to have some format and
>     semantics for the initData parameter of generateKeyRequest() and for
>     the key and initData parameters of addKey(). What format and semantics
>     do you plan to use for these? In particular, do you believe that what
>     you have chosen here is royalty-free? If you believe you have found a
>     royalty-free (but not clear key) initialization procedure, are you
>     willing to standardize it under the W3C Patent Policy?
> initData is container-specific, not CDM-specific: 
> http://dvcs.w3.org/hg/html-media/raw-file/tip/encrypted-media/encrypted-media.html#initialization-data. 
> I expect that ISO Common Encryption, WebM, etc. will define the format.
> key, which will often be a license, is CDM-specific. The format and 
> semantics will be up to the CDM providers. I don't object to 
> standardizing it, but I'm not sure of the value since it is likely 
> encrypted.

David, I'm hearing two things.

An informal disclosure request: "actual knowledge of a patent which the 
individual believes contains Essential Claim(s) with respect to the 
specification for which disclosure is requested."

Confirmation that the development of CDM "key systems" is covered by the 
W3C Patent Policy: should a company decide that they want to create 
their own CDM, and they do so, they should not face face IP litigation 
from W3C members. Each existing CDM vendor, who is also a w3c member, 
would check their patent holdings for relevant IP. A fictional example 
would be "Encryption of a network video stream and management of a 
collection of keys for decoding of the data".

My understanding is that companies should be able to create and maintain 
CDM providers without fear of competitive patent disputes.

Received on Monday, 12 March 2012 19:24:51 UTC

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