Thanks for the reply, this seems like a pretty strong game killer for captive portal. One of the main reasons I need to white list devices includes xbox live, and psn (student dorms). The PS3/PS4/360/XBone devices do not play nice with the captive portal at all. In fact the XBone requires you to sign in to xbox live before you can browse the web it seems, thus obviously you can bring up the captive portal page. I am considering trying to whitelist the xbox live and psn networks by host name to see if that helps…
EDIT: but of course while that will allows the devices to sign into the gaming networks, it wont allow other sites and services to work on those devices...