Re: Deciding Exceptions (ISSUE-23, ISSUE-24, ISSUE-25, ISSUE-31, ISSUE-34, ISSUE-49)

Sure.  As the spec current reads, third-party ad networks are allowed to serve contextual ads on sites even when DNT:1 is on, yes?  In order to do this, they're going to get log data, user agent string, device info, IP address, referrer url, etc.  There is growing recognition that that information in and of itself can be used to uniquely identify devices over time (http://www.networkworld.com/news/2012/020212-microsoft-anonymous-255667.html) for profiling purposes.  It was my understanding that one of the primary arguments against allowing third parties to place unique identifiers on the client was because of the concern that they were going to be secretly tracking and building profiles using those cookies.  My point is that they will be able to do that regardless, with little external ability to audit.  This system is going to rely to some extent on trust unless we are proposing to fundamentally rearchitecture the web.

The other argument that I've heard against using unique cookies for this purpose is valid, though to me less compelling: that even if just used for frequency capping, third parties are going to be able to amass data about the types of ads a device sees, from which you could surmise general information about the sites visited on that device (e.g., you are frequency capping a bunch of sports ads --> ergo, the operator of that device probably visiting sports pages).  Everyone seems to agree that it would be improper for a company to use this information to profile (meta-profile?), but there are still concerns about data breach, illegitimate access, and government access of this potentially revealing information.  This concerns me too, but the shadow of my .url stream is to me considerably less privacy sensitive than my actual .url stream.  I could be willing to compromise on a solution that allowed for using cookies for frequency capping, if there was agreement on limiting to reasonable campaign length, rules against repurposing, and a requirement to make an accountable statement of adherence to the standard.  I would be interested to hear if it would be feasible to not register frequency caps for ads for sensitive categories of information (or if at all, cap client-side), though again, it's important to keep in mind that that data may well be collected and retained for other excepted purposes under the standard (e.g., fraud prevention) --- cookie or not.  
  _____  

From: Jonathan Mayer [mailto:jmayer@stanford.edu]
To: Justin Brookman [mailto:justin@cdt.org]
Cc: public-tracking@w3.org
Sent: Thu, 09 Feb 2012 18:32:19 -0500
Subject: Re: Deciding Exceptions (ISSUE-23, ISSUE-24, ISSUE-25, ISSUE-31,         ISSUE-34, ISSUE-49)

Justin, could you explain what you mean here?
  
  Thanks,
  Jonathan
  
  On Feb 9, 2012, at 3:17 PM, Justin Brookman wrote:
  
  > the standard currently recognizes that third parties are frequently going to be allowed to obtain uniquely-identifying user agent strings despite the presence of a DNT:1 header