Here is my feedback on my first try at multiplayer in P3D v2.3. It was a bit complex but I succeeded and the experience was extremely nice. We were just two pilots, my brother and myself. I convinced my brother to buy P3D instead of FSX a few days ago, and in return he convinced me to try some formation flights in multiplayer.
There were a few prerequisites that made things more complex than they should be.
The main one is that, if I understood correctly, a direct IP connections requires all computers to be in LAN. Unfortunately, my brother leaves a few kilometers away from me, so we used a nice little freeware program (free for personnal use) named TeamViewer. This program can create a VPN to simulate a LAN. In the past for FSX I have been using Hamachi, but that program was more complex, and I heard that it recently became payware or something... TeamViewer was easier anyways, so we went for that one.
The fact that I was using a router (gateway?) for my internet connection also created some problems. I had to configure the router to properly forward a few ports, and I don't know if I really did everything correctly.... Anyways, in the end, I managed to create that VPN with my brother's computer and mine, and we finally managed to host a multiplayer session on his computer that I could see in the list of sessions to join. (The sessions I would host were not visible to him, for some reason... probably because of the router).
An important thing to say is that we were both flying with unlimited framerate in the graphical settings (and no external limiter in the drivers or anywhere). In FSX, this would have resulted in connection losses or strange aircraft movements (imprecise position, movement not fluid etc...), but in P3D, the connection has been rock-stable and the aircraft of the other player was also very stable with fluid movements. We were both using the default A-36 from Carenado for our first training, to avoid unecessary complexity. The flight was very nice, even though we flew over default scenery because my brother didn't have the time to download or install any additionnal sceneries yet. I provided him the link to the OrbX PNW demo, so I hope we will soon make some circuits around Bowerman together
(I mean, when he will finally be able to download it without seeing the download crashing around 35 MB size...)
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