We've been hearing about the exhaustion of IP4 addresses for years now, but that day has yet to come despite the periodic moments of hype. Of course, that is definitely coming. Recently a new threat to our beloved internet has been making the rounds: a capacity limit to the fiber optic network at the backbone of the web.
In the major hubs of the internet known as the backbone, high capacity fiber optic cables are used to transmit the vast amount of data that converges at these points. As the amount of traffic has increased over the years, the signal through the pipes has been amplified repeatedly to boost the amount of bandwidth they can carry. Different carriers are transmitted through the cables at different frequencies to allow for more simultaneous data transmission. The trouble is that the greater the number of beams of light introduced into a cable, the more "crosstalk" or interference that occurs. The physical limit of which has been reported to be about 100Tb/sec.
That sounds like a lot, 10TB of data per second, but recent estimations have us reaching that limit in as quickly as 5 years. This sparked a period of panic for a couple of months. That panic was short lived however as researchers all but solved the problem for the indefinite future soon after the release of the news.
Researchers at the University of California, San Diego have figured out a way to increase the power beyond the previous physical limit, therefore increasing bandwidth capacity and the distance the information can travel. What's more, their technique, reported in Science, effectively eliminates the need for costly electronic regenerators (signal repeaters) along the route, making the future of fiber optic transmission both faster and cheaper.
The crux of their breakthrough is in the realization that the distortion "crosstalk" is not chaotic or random - if follows the laws of physics. Knowing that, they figured out that the distortion can be predictable and therefore reversible at the receiving end of the transmission. Using what's called a frequency comb, the information at the transmitting side is purposely pre-distorted, but in a predictable way. The receiving end then reverses that distortion since it knows what to expect. This pre-distortion allows for the signals in the fiber optic cable to be amplified well beyond the current limitations since distortion is no longer a destructive factor.
Using this new technique, researchers were able to increase data capacity 20x and send transmissions over 7,400 miles without a signal repeater. Based on our current physical limitation of 100Tb/sec, that's a boost to 2000Tb/sec (aka 200TB/sec) which should extend our 5 year death march considerably. So fear not, the YouTube makeup how to videos will be just fine for a while longer.