1. Here's how cookie ID matching works:

3. Here's how cookie ID matching works if your cache is cleared of all cookies and you visit a website that will personalise ads to you:

Cookie ID matching example
  1. User requests to visit Website. Website has a cookie match tag. Ad space on Website is enabled for Real Time Bidding.
  2. Website renders and calls Ad Manager. Ad Manager selects Exchange. Exchange provides to Ad Manager a Cookie Matching URL to assist cookie match. Cookie Matching URL points to Exchange's own server. Ad Manager drops an empty 1x1 pixel on User browser. Pixel points to the Cookie Matching URL.
  3. Exchange's server identifies User. Exchange selects bidding partner (DSP) to match with User. Exchange redirects to selected bidding partner using Exchange's own cookie matching service. DSP redirects back to Exchange with user ID to be stored in the cookie match table.
  4. Ad buyers send bid request to DSP.
  5. DSP processes bid request and sends bid response to Ad buyers.
  6. DSP wins auction, sends to Ad buyer ad with an invisible match tag.
  7. Ad buyer serves to User DSP's ad with match tag and places ad manager cookie on User browser.
  8. Match tag calls Cookie matching service. Cookie matching service reads ad manger cookie in user browser.
  9. Cookie matching service sends to DSP a redirect with user ID.
  10. User browser loads DSP's URL.
  11. DSP generates and places a DSP cookie in match table of Cookie matching service (belonging to Exchange). Cookie matching service reads ad manger cookie. In match table, Cookie matching service matches User ID with DSP cookie to consider user information associated with the ad buyer cookie ID to make decisions about User identified by the User ID.
  12. DSP places DSP cookie in User browser.

4. Here's how cookie ID matching works if you continue to visit the same website and you have not cleared your cache of all cookies:

Ad buyer and Ad Manager cookies are already on the User machine:

  1. User requests to visit Website. Website has a cookie match tag. Ad space on Website is enabled for Real Time Bidding.
  2. Ad buyers send bid request to DSP. DSP receives the bid request.
  3. DSP consults User ID in match table of Cookie Matching Service to find the cookie earlier created to consider user information associated with the ad buyer cookie ID to make decisions about User identified by the User ID. DSP responds to bid request.
  4. DSP wins the auction.
  5. Ad is delivered to User.

5. How to find out about cookies on your site?

With Signatu's Trackerdetect you can detect, monitor and record all cookies on your site, including cookies set by 3rd parties.

See the Trackerdetect slides on Slidebean.