Ok, here is how the internet works.
Average Joe's internet(regular person)
Broadband cable is run into house>connects to modem>connects to wireless router so people have wi-fi>Laptop connects to wi-fi for internet.
My Internet
Broadband cable is run into house>connects to modem>Connects to my computer through an ethernet cable.
Therefore I have no router.(Well, I do, but I have to connect directly to the modem in order to get a blockland server working. My router can't port forward ;_;)
You dont have a router, but you do? ... your making no sense here.
The wires should be something like this:
Wall socket --> connect to cable modem
Cable modem --> connect to some box-like-thingy
box-like thingy --> your computer.
--or--
Wall socket --> connect to cable modem
Cable modem --> connect to some box-like-thingy with an antenna (wireless access point)
your computer connects over the wireless network.
if not, describe what you do have.
The "box-like-thingy" is your router. In order to do port forwarding correctly you will need:
a) the manual that came with the thing, then read on how to do port forwarding.
-or-
b) a long call to your ISP tech support if they are the ones who sold you the box-like-thingy.
-or-
b) goto your local computer store and REPLACE the thing with something that works (this will cost you around $20 - $40). i can offer suggestions if you choose this option.
For reference - this is my setup:
Wall socket --> cable modem (black box with green lights and says "comcast")
cable modem --> linksys router (grey+blue box with lots of plugs for wires)
router ---> laptop
router ---> desktop