Eventually the first settlements on Mars will need to have not only a Mars computer network (and eventually and Mars-based internet) but a way for that internet to connect / synchronize with the Earth-based internet.
I did some thinking and some research about what it might take to establish such a system. It turns out to be sorta complicated.
Radio communications break down not just according to the inverse square law, but due to interference and noise, more like the inverse quadratic law. So we’ll have to use lasers or something much more efficient.
There’s also the last mile problem. Until there is a series of geosynchronous satellites in low-Mars-orbit to deliver 100% coverage to the future settlements, we’re at the mercy of Mars’ orbit. The latest and greatest orbiters and rovers have pitiful data rates compared to what we have on Earth so the best approximations should assume we are able to deliver top notch communications equipment.
But even if we get state-of-the-art satellites in orbit around Mars, delivering 100% radio coverage to the settlements on the surface with state-of-the-art radio communications between them, and assuming we have an established internet infrastructure on the surface, there is still a delay in communications of between 3 and 21 minutes between the Earth and Mars, depending on the state of the planets in their orbits around the sun.
No realtime communication is possible. No video conferencing.
I wonder about the existing protocols that run our internet, and how they will handle such a delay. TCP breaks down when you have a high-latency, high-bandwidth connection (like this). All the existing space communication tech uses error correcting algorithms instead of error-detecting protocols to reduce both the amount of power required to transmit radio data and to reduce the need to re-send data.
Take Wikipedia. If I’m living on Mars, I almost certainly want access to the world’s most comprehensive store of human knowledge. Wikipedia is huge, and growing. Even if I just look at the English version of Wikipedia, it clocks in at about 44 million pages, occupying about 100GB compressed, and 10TB uncompressed.
The only realistic way to have such access is to maintain a local mirror of the site, which means servers on racks and lots of power connected to the local grid.
So that means we’re looking at infrastructure that synchronizes behind the scenes, rather than infrastructure that allows point-to-point communication. Or at the very least a hybrid system.
And this all assumes that we’ve already placed high-tech satellites in orbit around Mars, the likelihood of which is unclear. It may be that the early days of computing on Mars will be much more limited in scope, and the communication bottleneck with Earth will be exacerbated the more people use it.
But the great thing is that the original memo, The Intergalactic Computer Network, designed most of the internet protocols to work out of the box, assuming the hardware functions properly. And that’s pretty cool. You’ll literally be able to take your MacBook with you and it should work (assuming we solve the grounding problem).