mark through a single optical fiber. That’s enough data flow to download three seamless months worth of HD video in a single second.
The researchers used two different tricks to up their data rates, one altering the light itself, the other by carving up new channels within the fiber. The first approach, via NEC, notched 101.7 terabits per second over 100 miles using a novel scheme that stuffs pulses from 370 different lasers into the single pulse that reaches the end receiver.
Each laser emitted a slightly different frequency of light in the infrared spectrum, with things like amplitudes and polarities tweaked to make each of them different. So even though all 370 slivers were packed into the same pulse, each could code its own packet of information that could then be unpacked separately at the other end.
The other approach, from a team at Japan’s National Institute of Information and Communications Technology, was even faster. A standard fiber cable contains a single light-guiding core, so the researchers decided--logically enough--that seven cores would work even better. Their seven-cored cable can transmit 109 terabits per second (or 15.6 terabits per second per core), drastically improving capacity.
But don’t expect to see those kinds of speeds hitting your PC any time soon. For one, neither of these technologies is particularly easy to integrate into the current infrastructure, and difficulty notwithstanding there isn’t a real commercial need for these high capacities--they simply far outstrip commercial data demand.
But traffic is growing at a rate of something like 50 percent per year, thanks to TV-on-the-Web offerings like Netflix and Hulu, as well as cute puppy videos and Rebecca Black. One day we’ll need those data rates no doubt. In the meantime, these technologies will likely find work as short haul, high volume connections in places where their capacity can be put to use, such as server farms at Amazon.
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