w3ProfileId provides the ability to identify who is using your Web site. While the technology available within HTML doesn't allow identifying individual people, using cookies determines if the Web browser being used has previously accessed your site.
Each time a browser contacts a FlashConnect application, it provides a unique value (cookie) to FlashConnect. If it does not have a value to pass to FlashConnect, FlashConnect gives it a value to use in the future. This value is provided to the application in the w3ProfileId variable.
There are two ways of accessing the w3ProfileId variable:
Using the variable w3ProfileId as defined in w3Include.
Retrieving the CGI variable w3ProfileId using w3GetCGI(x, "w3ProfileId").
The differences are:
If the browser supplied a w3ProfileId, the value of w3ProfileId in named common and from CGI is the same.
If the browser did not supply a w3ProfileId, the value in named common is the value being passed back to the browser and the value from CGI is empty.
If the browser is not accepting cookies, all contacts look like the browser has never previously visited the site.