I think it more depends how big of *****s your Cable company are. Read your Terms of Service. I'm not sure what ports get filtered on my connection, but I've run webservers, ssh, microsoft vpn and IPSec vpns over it no problem. In fact, I don't think I've ever hit a roadblock yet with my packets. The only thing that ever screwed me was the fact that I have to upgrade to a business account and pay $25 more for a static IP, which states it can change. I'd try to test the waters by opening up the port for your vpn without it running and then have a friend ping it. It goes thru, your golden, if not then change the port. If your stuck with DHCP, get yourself a DynDNS account and have your router or computer automatically update it for you whenever it changes. You'll get a decent result. Not fantastic, but decent.