Geeking out over submarine cables

I’m having a lot of fun reading Pipe International’s blog documenting the process of building and deploying their PPC-1 undersea telecommunication cable. The cable is running from Sydney, Australia to Guam, where it will peer with other high-capacity submarine cables into various parts of Asia. It is fascinating to learn a bit more about the amazing advances in engineering that make the installation of a 6,500 kilometer long, 1.92 Terabit per second fiber-optic cable a reality. When it comes right down to it, they are building a massive infrastructure around a pair of tiny glass fiber cables that are each the width of a human hair. And through that itty bitty cable, they are able to pipe an amount of data equivalent to, oh, I dunno, some large number of Libraries of Congress per second. Or the example they use, a system that could accommodate the entire population of Australia simultaneously making overseas telephone calls.

Now, I know that a light channel that carries 10 gigabits per second needs to pulse ten billion times a second in order to work its magic, but I never really thought about that number: ten billion light pulses per second! And then, they multiplex it on different light wavelengths so that there are 96 simultaneous data streams, each 10 gigabits per second, which adds up to 960 gigabits per second, and then another cable doing the same thing in the other direction. All this over a fiber pair the width of a couple human hairs, traveling over six thousand kilometers over the ocean floor. And the time it takes for the data to get from Sydney to Guam? 35 milliseconds.

Yeah, when you think about it, its pretty damn cool.

One reply on “Geeking out over submarine cables”

  1. Really rather interesting. Never thought about the logistics of laying and undersea cable. I wonder how hard it is to splice the cable if it gets cut or damaged! I am thinking about several thousand feet below sea level.

    Just a thought.

Comments are closed.