Yesterday afternoon I met some of my squadron mates to fly some dogfights. One of them gave us his IP and we tried to connect through the Multiplayer Option in the game, but we couldn't. We decided that my PC would be the server, so I gave them my IP but we couldn't connect either. Eventually, the third mate gave us his IP and we could connect and fly at last. My doubt is, why couln`t they connect when I was the server? I had my Firewall off. I have got a Router. Is it necessary to open a specific port? Which one and how can I do it? If there is someone who knows anything about it, I would really apreciate any kind of help.