Tubes: A Journey to the Centre of the Internet. By Andrew Blum is an excellent introduction to the nuts and bolts of how exactly it all works. The term “internet” is a collective noun for thousands of smaller networks, run by corporations, governments, universities and private business, all stitched together to form one (mostly) seamless, global, “internetworked” whole. In theory, the internet is meant to be widely distributed and heavily resilient, with many possible routes between any two destinations. In practice, a combination of economics and geography means that much of its infrastructure is concentrated in a comparatively small number of places.
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