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Re: Privacy implications of automatic alternative selection (Re: Acessibility of <audio> and <video>)

From: Charles McCathieNevile <chaals@opera.com>
Date: Fri, 12 Sep 2008 01:48:59 +0200
To: "Henri Sivonen" <hsivonen@iki.fi>, "HTML WG" <public-html@w3.org>
Cc: "W3C WAI-XTECH" <wai-xtech@w3.org>, "Dave Singer" <singer@apple.com>
Message-ID: <op.uhccfxa8wxe0ny@widsith>

On Thu, 11 Sep 2008 19:38:21 +0200, Henri Sivonen <hsivonen@iki.fi> wrote:

> The privacy implications of using media queries came up on the telecon.  
> (The tacit assumption was that revealing that one has a given disability  
> is a privacy-sensitive matter.)
>
> The choice of alternative media streams gives the content provider  
> information that correlates with the user's disabilities (unless all  
> alternatives were downloaded so that the content provider couldn't tell  
> with alternative was actually consumed).
>
> If the user has to select from alternatives, the information about the  
> choice is leaked to the content provider at that point.
>
> Media queries (or any other automatic selection mechanism), on the other  
> hand, would allow content providers to probe the user's  
> disability-correlated settings when the user visits a page without  
> taking specific further action on the page.

But the content provider doesn't have to be a rocket scientist to discover  
that some set of users is requesting only certain parts of the content.  
And from there, with a simple login, it is easy for people at opera to  
discover that I prefer the transcript of a meeting video to the whole  
video.

Disability has nothing to do with it. Users request what they want at a  
given time. If I browse on my phone (and I do) then I make different  
choices about what I want from YouTube to the things I ask for on my PC.  
Ditto the difference between being on a fat pipe in the US or Norway and  
being on a slow dodgy connection in the places I spend most of my life.

As Raman said, an intelligently built site is not asking if I have a  
disability. It may be that the user selects the same thing always, and  
sets up their browser to automate that. Or it may be that they select  
different things depending on where they are and what they are doing (a  
high-quality braille display at a University Office is not the same as a  
screen-reader on a shared computer-centre machine, before we even consider  
something other than blindness).

People are not interested to tell you their life history, they are trying  
to get a usable form of a meeting record, or a tax form, or some book to  
read their kid, or some movie their kid has been bugging them to find.

cheers

Chaals

-- 
Charles McCathieNevile  Opera Software, Standards Group
     je parle français -- hablo español -- jeg lærer norsk
http://my.opera.com/chaals   Try Opera 9.5: http://www.opera.com
Received on Thursday, 11 September 2008 23:50:01 GMT

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