W3C home > Mailing lists > Public > ietf-http-wg-old@w3.org > January to April 1997

Re: Unverifiable Transactions / Cookie draft

From: Koen Holtman <koen@win.tue.nl>
Date: Mon, 17 Mar 1997 23:17:05 +0100 (MET)
Message-Id: <199703172218.XAA21516@wsooti08>
To: Dwight Merriman <dmerriman@doubleclick.net>
Cc: http-wg@cuckoo.hpl.hp.com, dmk@allegra.att.com, montulli@netscape.com, yarong@microsoft.com
X-Mailing-List: <http-wg@cuckoo.hpl.hp.com> archive/latest/2751
Dwight Merriman:
>I'd like to bring up one another (small) point.
>Virtually all banner advertising on the web relies on redirects for
>click-throughs so that click rates can be measured.  This means that the
>redirection to the advertiser's web site will always be an unverifiable

The redirection won't be unverifiable if the script which does the counting
and redirection to the page is on the target site already.

>So, when a user visits an advertiser's site directly, cookie assignment on
>the home/jump page is possible, whereas when the user visits the page via
>an advertisement, it will not be possible.

Yes, if the script is on the site which served the banner.  But I don't see
this as a big problem.

>Designers of web sites (at least the large percentage who will advertise on
>the web) will have to take into account that cookie assignments on their
>home page may fail a large percentage of the time.  If they wish to measure
>number of unique visitors to their site, they will get a highly inaccurate
>reading since often multiple cookies will be assignied to a single user
>before one "sticks".

Some careful design can work around this: suppress assignment of cookie if
the referer field shows that the user comes from the click-through script.

Note however that higly inaccurare readings are almost guaranteed anyway
because many people disable cookies, or have browsers which do not support

>This is not a major flaw, but it is inelegant, and I just want to make sure
>everyone has considered this.

Received on Wednesday, 19 March 1997 02:05:22 UTC

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