Have you ever wondered how the Internet flows? Here are a couple of fantastic maps: of transoceanic cables and of public Internet links.
The first one (http://submarine-cable-map-2014.telegeography.com/
) shows the lines that span the oceans; these are where almost all of the data flows from country to country. (Satellites are actually far less useful in the modern age; their bandwidth is a small fraction of what cables can provide) Fishing nets and ship anchors are the biggest threats to their day-to-day function, and for countries which only have one or two links, a single accident can easily have a huge impact. While it may not surprise you that much of Africa and South Asia are poorly connected, you may be surprised at how few lines flow in to Australia.
The second map (http://global-internet-map-2012.telegeography.com/
) shows public interconnect lines and bandwidth. This map is a bit older (2012) but it shows a lot of the real connectivity problems very vividly: North America, Europe, and the Middle East are well-connected, but Asia (except for a few major cities), Africa, and South America fare much worse. To see the real problems, zoom in carefully and try to trace (say) the shortest route you can find from Mumbai to Bangalore. You're not hallucinating: It's via Singapore. This is actually a big improvement; until a few years ago, it was via Zurich. In South Asia and South America, ISPs are sort of infamous for saying "this neighboring ISP is my competitor! Why would I peer [connect networks] with them?" In the rest of the world, everyone connects with everyone -- that's why the network is fast and robust.
I'm not sure if this second map includes private networks or not; I suspect it doesn't, which actually hides a huge fraction of the Internet which you use. For example, when you connect to Google, you're really connecting to the nearest Google endpoint, and then all of the rest of the traffic (to wherever your e-mails, posts, videos, and so on are living) is routed over a very
big network that we run -- and which is much faster than the public network, because it's used by a single organization which can carefully control and synchronize traffic.
h/t +Kristin Milton
for leading me to these.