I think TCP window scaling is supposed to deal with that. But I have also heard that computers used on ISS supposedly all do remote destktop to computers on the ground when they need any outside communication. But I don’t recall the source, so I am not sure if this is accurate. Speaking of 1+ sec latency, some point in the past year I discovered that BIND 9 would completely fail to perform recursive lookups once latency exceeded 1 second. That came as a surprise to me as prior to that my experience had been that it was a robust DNS implementation.