A method is provided, including the following method operations: accessing a first web page associated with a first domain using a browser of a device; in response to the accessing the first web page, accessing an identity server to retrieve an identifier for the browser that accessed the first web page, the identifier being stored to a local storage of the device; accessing a second web page associated with a second domain using the browser; in response to the accessing the second page, accessing the local storage of the device to retrieve the identifier; wherein accessing the first web page and accessing the second web page are associated to the identifier.