Suppose mankind never developed spaceflight, which precludes any form of space-based stations or satellites. How could a single global Internet be achievable as we know it today? What technologies would need to be developed/utilized to allow the Internet to be available, reliable, and maintainable across oceans, mountains, and other terrain?
Submarine communications cable can cross oceans just fine, no space technology necessary. Started in 1853.
Mountains and other terrains is just hassle. Cable is easy to lay and easier to repair - but repairing even sea cable is possible, see link above.
Pipeline is harder but also possible overland, over or around any terrain.
Satellite in geostationary orbit is 50K km away. Round-trip is 100K km. More than twice than distance around the world.
Few cool factoids:
- 99% of international data is transmitted by submarine cables, which are as thin as Magic marker pen;
- and are sometimes bitten by sharks, and routinely tapped (in international waters) by spy agencies.
- undersea cables (technology older than telephone) are faster and cheaper than satellites.
- easiest way to wage cyber warfare is in scuba gear using wire cutters.
- almost 10% of cables are "spare" - laid but not used.