Why is my PS3 having connection issues?

I have been having internet issues with my PS3 for a while now. I am beginning to think it is my ISP. All my correct ports are open, firmware on the router is up to date, and anything else that may get in the way. I have looked up this problem numerous times and all the solutions that worked for other people have not for me. I have been using Call of Duty: Black Ops as a litmus, and other games have proven to work similarly. Before the problems occurred, the game would say my NAT type is Open and I would have little or no lag problems. A few months back the game started saying NAT Type: Moderate with the message saying that matchmaking may take longer, well my lag would skyrocket in game and the bars would be red and yellow, despite the fact that my PS3 internet connection test says I have decent Up and Down speeds. It also says that my NAT Type is Type 2, so what is the deal? could this be a ISP issue, Modem issue, can I fix this so I can play future games online without having to go to my ISP?