The Blaugh

Althoug I have known how the world is cabled together and that there are huge pipes on which we transfer tons of data, I didn’t know the extent of it and how long those have been in existence. So when I read this article I was totally blow away by the fact that the first cables were put down in the 1860’s and by early 1900’s most of the continents were cabled up by the British empire. Totally amazing.

cross section of a submarine communications cable.
1 – Polyethylene
2 – Mylar tape
3 – Stranded steel wires
4 – Aluminium water barrier
5 – Polycarbonate
6 – Copper or aluminium tube
7 – Petroleum jelly
8 – Optical fibers

As far as laying a submarine cable, specialized cable-laying ships must be used — and again, when a cable is broken (usually by a trawler, but sometimes a whale!), another special ship must be used. This generally means that laying a cable is logistically challenging and very expensive — and when a cable breaks, it sometimes isn’t possible to fix it immediately if a cable-fixing ship isn’t nearby (and for this reason, most submarine cables use a ring topology in case one stretch is broken).

Further reading:

1. Secret World of Submarine Cables
2. Wikipedia: Submarine communications cable