Ad-hoc means that it's meant to be played between 2 PSPs connected together in close range. As for playing over the internet, you could probably find more information on team X-link's site (
http://www.teamxlink.co.uk/) and possibly a list of compatible PSP games. I'm not too familiar with Kai for PSP so it might add the possibility of playing adhoc games over the net. Either way, you should check out the site.
