Re: de-identification text for Wednesday's call

then what are you retaining and using the data for?

On Apr 2, 2013, at 11:03 AM, Shane Wiley <wileys@yahoo-inc.com> wrote:

> Dan,
>  
> Once the one-way hash is applied (and other elements of record appropriately cleansed) the data is moved to a system that is not allowed to be accessed externally.  Its these operational and administrative controls that are essential to ensure de-identified data is not re-identified at some later time.  I believe you’re looking only at the technical merits which is only seeing a small portion of the overall solution.
>  
> - Shane
>  
> From: Dan Auerbach [mailto:dan@eff.org] 
> Sent: Tuesday, April 02, 2013 10:59 AM
> To: public-tracking@w3.org
> Subject: Re: de-identification text for Wednesday's call
>  
> On 04/02/2013 08:50 AM, Shane Wiley wrote:
> once the one-way hash function has been applied the data is never again able to be accessed in real-time to modify the user’s experience.
> I think I'm confused, can you explain this more? How is this possible? If you are just hashing a cookie string, your web server receives a request that includes a cookie string, you hash that cookie string (which is in incredibly fast operation), match the hashed cookie against the stored data, and return personalized results.
> 
> Or are you salting the hash differently for every request, or combining the cookie with an ephemeral piece of data (the timestamp) before hashing and then throwing away the timestamp?
> 
> Thanks for clarifying, apologies if I'm just being dense.
> 
> Dan
> 
> 
> -- 
> Dan Auerbach
> Staff Technologist
> Electronic Frontier Foundation
> dan@eff.org
> 415 436 9333 x134