My understading is that the "Tmobile Web" is for connecting to web servers only, so ports 80 and 443 should be fine. But, in order to not violate your terms of service, if you want to connect to other ports (say, ssh from your tablet to an ssh server), you'd need the "total internet" package. Some ports to try: ssh, imap, imaps, smtp, imap, imaps, pop, spop or, try to skype from your tablet.