- From: Rob van Eijk <rob@blaeu.com>
- Date: Fri, 19 Jul 2013 19:35:07 +0200
- To: "Mike O'Neill" <michael.oneill@baycloud.com>
- Cc: "'Ronan Heffernan'" <ronansan@gmail.com>, "'Tracking Protection Working Group WG'" <public-tracking@w3.org>
Ronan, How is an identifier in the browser remaining the same over a period of 6 months proportionate to the purpose of audience measurement? If a campaign runs over 53 weeks, would you plan to resurrect the identifier once a user clears the cookie? Or keep track of different identifiers that can be connected to a period of 53 weeks? I am slowly getting confused and concerned of what is really needed on a technical level for audience measurement... Rob Mike O'Neill schreef op 2013-07-19 18:30: > Hi Ronan, > > No, not a unique identifier, which I agree would diminish privacy and > should be ruled out along with any other tracking identifier > collection when DNT is 1. What I meant was a count value (number of ad > impressions) which I assume would have limited entropy i.e. the max > value would be << the number of online individuals in scope. How many > ad impressions would you need to count? I agree relying on the cache > for 6 months would be a stretch, but do you need to do that? At some > point there may be some loss of functionality when DNT is 1 but the > setting is an important indication of user intent so needs to be > honoured. > > How an ETag is generated in not specified in the HTTP spec, so in what > way would this be "improper"? > > Mike > > . > > FROM: Ronan Heffernan [mailto:ronansan@gmail.com] > SENT: 19 July 2013 15:54 > TO: Mike O'Neill > CC: Tracking Protection Working Group WG > SUBJECT: Re: issue-25 > > Mike, > > I am not sure that I understand your proposal, but it looks like you > are trying to (mis-)use the If-Modified-Since header in conjunction > with a small (improper) ETag value to forge a unique identifier. Is > that right? How is that an improvement? Do you expect that those > values will be maintained in the browsers for more than 6-months? > > --ronan > > On Thu, Jul 18, 2013 at 4:42 PM, Mike O'Neill > <michael.oneill@baycloud.com> wrote: > > Hi Ronan, > > I had another thought about frequency capping. If you use the > ETag/If-None-Match to contain a low entropy count value, 0..7, you > could combine that with the If-Modified-Since header to give you > unique visitor detection *and* frequency counting, without a > persistent UID in a cookie or anywhere else, and without JS. > > You could do that in your 1x1 gif handler and not need the iframe (or > the v60.js script tag that I notice imrworldwide.com [1] - a Nielsen > domain, uses sometimes). > > If you did that (in the DNT:1 case), you would not need a permitted > use. > > Mike > > > > Links: > ------ > [1] http://imrworldwide.com
Received on Friday, 19 July 2013 17:35:44 UTC