GTM doesn't know about URL's. It only knows about DNS requests. And only if the users have different LDNS (Local DNS) servers can GTM make a decision... When GTM gets the request, all it knows is the IP address of the client LDNS server. It doesn't know the clients actual IP address. So if your clients all happen to use the same DNS server, GTM has no way to know anything different about them.
However if your resource is on LTM, then the LTM can make a decision based on which client it is using something like a cookie etc... You can see this happening with some global sites that give you a local page based on a cookie that was set previously...
H
Nimbostratus
