Redundancy and restoration in the cable network

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The reason most cable breaks are invisible, and the reason a few are catastrophic. There are between about 150 and 200 cable faults somewhere in the world every year — roughly three a week — and almost none of them makes the news, because international traffic is routed over many systems and a carrier that loses one path restores its traffic onto another within minutes. That restoration is bought, planned and rehearsed: capacity is held on other systems for exactly this purpose. But redundancy is a property of the route, not of the contract. Buying capacity on two cables gives no protection if both lie in the same corridor, land at the same station, or cross the same strait, and it gives no protection at all if the total spare capacity on surviving routes is smaller than the traffic that has to move onto them. That is why an incident becomes visible in exactly two circumstances: when several cables in one corridor fail together, and when a place has few enough cables that losing one or two removes most of its capacity. Both conditions describe geography rather than technology, and both are the reason this Journey is about places.

A node is not a place. Drawing it on a map would assert something about the world that no stored fact supports.