I saw a map of undersea internet cables the other day and it’s crazy how many branches there are. It got me wondering - if I’m (based in the UK) playing an online game from someone in Japan for example, how is the route worked out? Does my ISP know that to get to place X, the data has to be routed via cable 1, cable 2 etc. but to get to place Z it needs to go via cable 3, 4?
it’s not efficient from the perspective of organization. But the thing nobody tells you here is that packets have no predefined route, they take whatever route gets them there optimally. So it’s highly redundant, and very fault tolerant. When you consider that, for what it does, it’s a highly efficient routing system.
To the point where you could cut an undersea cable, and traffic would still route perfectly fine, albeit probably a lot slower, assuming that isn’t your only connection of course. The fact that it works it all is kind of a miracle.