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Wouldn't light-speed internet be useful ? I would think that HFT firms would be interested in them

by Faaak 8y ago

coldtea 8y ago
We already have "light-speed internet" or close enough. Signals in cables travel at (approximately) light speed (for the medium, which is not vacuum). And we do have wireless EM signals and fiber optics cables as well...
- Faaak 8y ago
  The velocity factor is around 2/3 in optical fiber. That's slow to HFT firms. For example, the delay compared to vacuum/c would be of of 2ms for a 1000km link. And that does not take into account fiber repeaters or microwave links
  - DmenshunlAnlsis 8y ago
    You’d basically need a 1000km vacuum chamber to achieve that, which would be insanely expensive and an engineering miracle. I’m not even getting into what you’d be using as a transmission medium, because the vacuum chamber is prohibitive enough.
    - ttsda 8y ago
      You could use LEO satellites, add a few km up and down but you have way less hardware to pass through.
      - DmenshunlAnlsis 8y ago
        That’s a good point, the difference between vacuum and atmosphere isn’t so significant, but then it’s not really a new tech or “lightspeed internet” it’s just a satellite link.
        ttsda 8y ago
        With the addition of satellite-to-satellite optical connections, which will greatly improve latency and bandwidth.
        DmenshunlAnlsis 8y ago
        If SpaceX pulls off their swarm of telecom satellites, we might get to see how it really works in widespread practice. Exciting prospect!
        ttsda 8y ago
        Indeed. And what I'm most interested in is all the cash they're dumping into commercial phased-array antennas. If they manage to scale enough to get them to a low enough price they will be amazing for all sorts of other stuff.
    - petters 8y ago
      No, there is hollow fiber for communication. https://gizmodo.com/5992303/hollow-fiber-optic-tunnels-can-blast-data-at-practically-the-speed-of-light https://gizmodo.com/5992303/hollow-fiber-optic-tunnels-can-b...
      - DmenshunlAnlsis 8y ago
        but also reasonably low data loss of 3.5 dB/km. That still adds up at a distance though, so these crazy fast cables are most likely destined for supercomputer and data center applications, for now at least. Not really for communication, and I suspect that if you want it to scale up to 1000km, it’s going to strongly resemble the vacuum chamber I mentioned.
  - black_puppydog 8y ago
    If they're the only people interested in that, I'm okay with staying at 2/3...
  - coldtea 8y ago
    >That's slow to HFT firms. That's because we allow them to trade at such rates and compete on speed. A mere few decades to half a century ago we have 1/10 to 1/1000 the speed, and trading was going on just fine... I'd opt for a "turn based" trading system (with a small, but not tiny turn window), to eliminate any transmission speedup advantage from different traders.

Wouldn't light-speed internet be useful ? I would think that HFT firms would be interested in them

by Faaak 8y ago

Wouldn't light-speed internet be useful ? I would think that HFT firms would be interested in them

We already have "light-speed internet" or close enough. Signals in cables travel at (approximately) light speed (for the medium, which is not vacuum). And we do have wireless EM signals and fiber optics cables as well...

Faaak 8y ago
The velocity factor is around 2/3 in optical fiber. That's slow to HFT firms. For example, the delay compared to vacuum/c would be of of 2ms for a 1000km link. And that does not take into account fiber repeaters or microwave links
- DmenshunlAnlsis 8y ago
  You’d basically need a 1000km vacuum chamber to achieve that, which would be insanely expensive and an engineering miracle. I’m not even getting into what you’d be using as a transmission medium, because the vacuum chamber is prohibitive enough.
  - ttsda 8y ago
    You could use LEO satellites, add a few km up and down but you have way less hardware to pass through.
    - DmenshunlAnlsis 8y ago
      That’s a good point, the difference between vacuum and atmosphere isn’t so significant, but then it’s not really a new tech or “lightspeed internet” it’s just a satellite link.
      - ttsda 8y ago
        With the addition of satellite-to-satellite optical connections, which will greatly improve latency and bandwidth.
        DmenshunlAnlsis 8y ago
        If SpaceX pulls off their swarm of telecom satellites, we might get to see how it really works in widespread practice. Exciting prospect!
        ttsda 8y ago
        Indeed. And what I'm most interested in is all the cash they're dumping into commercial phased-array antennas. If they manage to scale enough to get them to a low enough price they will be amazing for all sorts of other stuff.
  - petters 8y ago
    No, there is hollow fiber for communication. https://gizmodo.com/5992303/hollow-fiber-optic-tunnels-can-blast-data-at-practically-the-speed-of-light https://gizmodo.com/5992303/hollow-fiber-optic-tunnels-can-b...
    - DmenshunlAnlsis 8y ago
      but also reasonably low data loss of 3.5 dB/km. That still adds up at a distance though, so these crazy fast cables are most likely destined for supercomputer and data center applications, for now at least. Not really for communication, and I suspect that if you want it to scale up to 1000km, it’s going to strongly resemble the vacuum chamber I mentioned.
- black_puppydog 8y ago
  If they're the only people interested in that, I'm okay with staying at 2/3...
- coldtea 8y ago
  >That's slow to HFT firms. That's because we allow them to trade at such rates and compete on speed. A mere few decades to half a century ago we have 1/10 to 1/1000 the speed, and trading was going on just fine... I'd opt for a "turn based" trading system (with a small, but not tiny turn window), to eliminate any transmission speedup advantage from different traders.