I tried a game between two physical machines using a null-model cable the other day. I was surprised by how technical it was. It CAN be done much easier – other programs of the era could communicate via serial and were almost entirely self-configuring. Basically PnP.
I had to set the speed in Wacky Wheels down to a ludicrous 9600 baud. Higher than that and the droupouts were unacceptable, causing the games to quickly become desynced, or they just wouldn’t connect at all.
The two computers, I might add, were right next to each other and the cable is I think about 1 metre long. (Maybe my cable just needs a ferrite bead?)
This might also explain why the physics are so granular – too many floating point coordinates would probably just make multiplayer completely unplayable due to sync issues.
