5 ms·

Oh wow. No guarantees, but they mentioned they achieved this on a single wavelength, and that wavelength multiplexing should be possible. Current Dense Waveleng

Oh wow. No guarantees, but they mentioned they achieved this on a single wavelength, and that wavelength multiplexing should be possible. Current Dense Wavelength Division Multiplexing (DWDM) supports something like 160 channels. If they are able to combine both of these technologies - theoretically you are looking at nearly 250 Petabits per second on a single fiber strand. Thing is, no one is pulling a single fiber cable. Modern fiber cables can contain up to a thousand fiber strands in a single cable although the highest strand-count single-mode fiber cable commonly manufactured is the 864-count, consisting of 36 ribbons each containing 24 strands of fiber. Even oceanic cables frequently have 48 or 96 fibers. That means, again theoretically, a land based 864-core cable can carry over 200 exabits per second, and an oceanic 96-core can carry 23.5 exabits per second. That's bananas. Edit: Very large numbers are hard for humans to grok. Some context on 200 exabits - There are 335,591,597 people in the United states. If you were to divide the bandwidth evenly between all those people, each person would have approximately a 600 gigabit connection. An UHD Blu-ray (4K, HDR) movie is about 50GB. On this connection you could transfer that in under 1 second (hand waving away overhead, write limitations and connection/handshake delays).

shalmanese 4y ago
> That means, again theoretically, a land based 864-core cable can carry over 200 exabits per second, and an oceanic 96-core can carry 23.5 exabits per second. That's bananas. The total amount of data generated per day is estimated to be 97 zetabytes [0] which is only 9 exabits per second. You could run the entire internet off a single cable that winds its way around to every single person and they could just siphon off the data they need. [0] https://www.statista.com/statistics/871513/worldwide-data-created/ https://www.statista.com/statistics/871513/worldwide-data-cr...
- gpderetta 4y ago
  Next question is, how long does the cable need to be to store the content of the entire internet and get rid of any other storage?
  - tecleandor 4y ago
    The entire internet as a circular buffer in a very long fiber cable. Just wait for your content to appear. :)
  - iso1631 4y ago
    https://live-counter.com/how-big-is-the-internet/ https://live-counter.com/how-big-is-the-internet/ puts the size about it at 23 million PBytes. 1000PB = 1EB, so 23,000 Exabytes At 200 exabits per second, or 25 Exabytes per second, it would take you a thousand light seconds to send the entire contents of the internet. With the speed of light in the cable about 2/3rds of C, that would require about 600 light seconds of cable, which is about the distance from the sun to the earth.
    - gh02t 4y ago
      Quick googling tells me the typical diameter of an undersea cable is 25 mm. If we assume let's say 15 mm of that is actual fiber (wild guess) and approximate them as a single cylinder that works out to only about 0.03 km^3 of glass... that's a lot more feasible than I was expecting. Comparable to the volume of concrete used to build the Three Gorges Dam. I suppose it's only that "reasonable" because we're talking about a hypothetical 200 exabits/s, puts into perspective just how fast that is. https://www.wolframalpha.com/input?i=pi+*+%28%2815%2F2%29+millimeters%29%5E2+*+%28600+light+seconds%29 https://www.wolframalpha.com/input?i=pi+*+%28%2815%2F2%29+mi...
  - derkades 4y ago
    Related video, using pings to store data: https://www.youtube.com/watch?v=JcJSW7Rprio https://www.youtube.com/watch?v=JcJSW7Rprio
taldo 4y ago
Subsea cables usually have 4 or so fibers, since they need repeaters every so many km, which drives the cost-per-fiber (the actual strand of glass is approximately free for all practical purposes).
- krisroadruck 4y ago
  This may have been true in the past but new subsea cables are not this limited. As an example the Dunant transatlantic long haul Google put in place in 2018 (went live in 2020) has 12 pairs (24 fibers). Grace Hopper, due online this year has 32 fibers. But your point stands - I should have said "up to" instead of "frequently".
  - waltbosz 4y ago
    The cable is named for computer science pioneer Grace Brewster Murray Hopper (1906–1992), best known for her work on one of the first linkers (compilers), which was critical in the development of the COBOL programming language. She’s also credited with famously finding an actual “bug” in a program; her team tracked down the source of a short circuit on the early Harvard Mark II computer to a moth trapped in a panel. It is to honor Grace Hopper’s legacy of innovation by investing in the future of transatlantic communications with a state-of-the-art fiber optic cable. https://www.submarinenetworks.com/en/systems/trans-atlantic/grace-hopper https://www.submarinenetworks.com/en/systems/trans-atlantic/... It's like having a highway named after you, only cooler, because it's data traffic, not automobile traffic.
  - taldo 4y ago
    TIL, thanks. I was at Google around the time Curie was being built and coming online (ca. 2018-2019, I think), and it has 4 pairs. I misremembered it being 4 fibers.
deleted 4y ago
[deleted]

shalmanese 4y ago

> That means, again theoretically, a land based 864-core cable can carry over 200 exabits per second, and an oceanic 96-core can carry 23.5 exabits per second. That's bananas. The total amount of data generated per day is estimated to be 97 zetabytes [0] which is only 9 exabits per second. You could run the entire internet off a single cable that winds its way around to every single person and they could just siphon off the data they need. [0] https://www.statista.com/statistics/871513/worldwide-data-created/ https://www.statista.com/statistics/871513/worldwide-data-cr...

gpderetta 4y ago
Next question is, how long does the cable need to be to store the content of the entire internet and get rid of any other storage?
- tecleandor 4y ago
  The entire internet as a circular buffer in a very long fiber cable. Just wait for your content to appear. :)
- iso1631 4y ago
  https://live-counter.com/how-big-is-the-internet/ https://live-counter.com/how-big-is-the-internet/ puts the size about it at 23 million PBytes. 1000PB = 1EB, so 23,000 Exabytes At 200 exabits per second, or 25 Exabytes per second, it would take you a thousand light seconds to send the entire contents of the internet. With the speed of light in the cable about 2/3rds of C, that would require about 600 light seconds of cable, which is about the distance from the sun to the earth.
  - gh02t 4y ago
    Quick googling tells me the typical diameter of an undersea cable is 25 mm. If we assume let's say 15 mm of that is actual fiber (wild guess) and approximate them as a single cylinder that works out to only about 0.03 km^3 of glass... that's a lot more feasible than I was expecting. Comparable to the volume of concrete used to build the Three Gorges Dam. I suppose it's only that "reasonable" because we're talking about a hypothetical 200 exabits/s, puts into perspective just how fast that is. https://www.wolframalpha.com/input?i=pi+*+%28%2815%2F2%29+millimeters%29%5E2+*+%28600+light+seconds%29 https://www.wolframalpha.com/input?i=pi+*+%28%2815%2F2%29+mi...
- derkades 4y ago
  Related video, using pings to store data: https://www.youtube.com/watch?v=JcJSW7Rprio https://www.youtube.com/watch?v=JcJSW7Rprio

taldo 4y ago

Subsea cables usually have 4 or so fibers, since they need repeaters every so many km, which drives the cost-per-fiber (the actual strand of glass is approximately free for all practical purposes).

krisroadruck 4y ago
This may have been true in the past but new subsea cables are not this limited. As an example the Dunant transatlantic long haul Google put in place in 2018 (went live in 2020) has 12 pairs (24 fibers). Grace Hopper, due online this year has 32 fibers. But your point stands - I should have said "up to" instead of "frequently".
- waltbosz 4y ago
  The cable is named for computer science pioneer Grace Brewster Murray Hopper (1906–1992), best known for her work on one of the first linkers (compilers), which was critical in the development of the COBOL programming language. She’s also credited with famously finding an actual “bug” in a program; her team tracked down the source of a short circuit on the early Harvard Mark II computer to a moth trapped in a panel. It is to honor Grace Hopper’s legacy of innovation by investing in the future of transatlantic communications with a state-of-the-art fiber optic cable. https://www.submarinenetworks.com/en/systems/trans-atlantic/grace-hopper https://www.submarinenetworks.com/en/systems/trans-atlantic/... It's like having a highway named after you, only cooler, because it's data traffic, not automobile traffic.
- taldo 4y ago
  TIL, thanks. I was at Google around the time Curie was being built and coming online (ca. 2018-2019, I think), and it has 4 pairs. I misremembered it being 4 fibers.

deleted 4y ago

[deleted]