I recently finished setting up SSH'ing to my Ubuntu-based server (thanks @Spiff) in terms of the port forwarding aspect. He told me that when remotely connecting, I need the router IP (aka NAT Gateway address). I have a Linksys EA7500. I went to Linksys Smart Wifi and opened the connections tab. I looked around to try and find something with NAT, when I came across the Advanced Routing tab. Heres a screenshot: So what do I need to do to find this router address? Thank you very much!
You should indeed cross check it with one of the websites (e.g. just google "whatsmyip") that tells you your public IP. If they don't match, it means that you are probably sharing it with other customers of your ISP and hence cannot use it to connect to one of your machines. (It could be because you are chaining routers or so as well though.)
Go to http://ipchicken.com to see your external IP address.