Server Connection Issues

Let me start off by saying that this community here is fantastic. Everyone here has been extremely helpful since I've been a member, and it's quite nice. I have a question, which I'm sure a lot of you have already addressed, but I'm kind of stuck in a situation...

Before moving, I had hosted a fairly nice server for about five months, learned the ropes fairly quickly, and was and still am quite familiar with how to run servers; however, I've run into a bit of a problem here.

Before I moved, I was using Comcast which I soon realized violated ToS for running a server. I never had problems, learned to port forward, easily did so with my Belkin router to the standard 25565 port.

When we moved, we upgraded to Comcast Business Class. I've tried the same methods as before when setting up servers, and I can't have anyone but myself connect to them now. I can only use localhost to connect. I'm still using the same router, so the same method still applies.

I'm not quite sure what my problem is, or what course of action I should take.

Thanks for your guys help!