Cross Domain Tracking will be wroken.
I have a question, after realizing the Crossing Domain Tracking so that a user accesses the Site A and then Site B is it accounted for as same user through the Client ID of the user, I have this scenario for example when the user click on the button register which is on www.domain1.com goes to the site wwww.domain2/example/main.aspx? ga = 1.202027665.1453627816. 1459363402 and that maintains the traceability of a site to another , but when the user for some reason tries to erase of the URL the clienteID (ga = 1.202027665.1453627816. 1459363504) and only is www.domain2.com/example/main.aspx, shown as a new session and is broken the Crossing Domains. Will there be way of controlling this?
Re: Cross Domain Tracking will be wroken.
the situation which you described would be really hard to reproduce as the _ga parameter is automatically added to the endpoint - the xdomain. The user does not really have any control over it.
The point of xdomain tracking i snot only to preserve the user but more importantly to preserve the session while moving through domains. So when a user gets to siteA and links to siteB.com/?_ga=124323423 GA consideres this as the same user same session. Without it, if a new visitor which does not have preset cookies on both domains, would be treated as new user and new session.
You can try to track this behavior in terms of tracking the referrer - so if a referrer to siteb is sitea but does not contain the linker parameter you would push an event which you can use to report these issues and further debug and fix the situation.