Environment
Adobe Experience Cloud
Issue/Symptoms
How does the Marketing Cloud ID Service maintain a consistent Marketing Cloud ID across domains in a browser that accepts third-party cookies?
Steps to Resolve
VisitorAPI.js
file loads and checks to see if an AMCV cookie exists on the current domain (SiteA.com). No AMCV cookie exists on the current domain, so VisitorAPI.js
checks to see if a demdex.net
cookie exists. It does not.dpm.demdex.net
with your Marketing Cloud Organization ID (also known as an IMS org ID). In this case, 1234@AdobeOrg is sent with the request.demdex.net
server receives the request and generates a UUID. Next, it uses the UUID and IMS org ID (1234) to generate the MID value.VisitorAPI.js
library writes the MID to an AMCV cookie in the browser. As part of the response, the demdex server also writes the UUID to a cookie. The AMCV cookie is written on the current domain (SiteA.com) and the demdex cookie is written on the demdex.net
domain.VisitorAPI.js
checks to see if an AMCV cookie exists on the current domain (SiteB.com). No AMCV cookie exists on this domain, so VisitorAPI.js
checks to see if a demdex.net
cookie exists. It does exist, so the value is retrieved.dpm.demdex.net
with the IMS org ID (1234) and the UUID value (ABCDE).VisitorAPI.js
library writes the MID (ABC1234) to an AMCV cookie in the browser. The AMCV cookie is written on the current domain (SiteB.com).