7 ms·

I remain convinced that this is Starlink's short-term customer if their promises are true. They are doing transmission via optical as the crow flies. If they're

by sargun 6y ago

I remain convinced that this is Starlink's short-term customer if their promises are true. They are doing transmission via optical as the crow flies. If they're doing O-O, or even low latency O-E-O, they can beat transatlantic fiber. For HFT houses, that's potentially a major edge.

ncmncm 6y ago
Starlink might get as much for denying access to specific other parties as for selling access in the first place.
modeless 6y ago
Starlink latency would be worse than shortwave. The advantage would be bandwidth, but I doubt that high bandwidth is really helpful for this application, especially if you have to give up a tiny bit of latency for it. After all, you can already have all the bandwidth you want with only slightly higher latency.
- hef19898 6y ago
  If memory works well, they have dedicated glass fibre for bandwidth, at least between Chicago and NY. Took the closest possible distance. Microwave is used for speed, in addition, to get binary signals from A to B. I heard that theory more than once about Starlink, it just doesn't make that much sense to me. Starlink could also be, of course, a clever way of getting a) enough launches to make reusable rockets financially feasible and/or b) getting financing for SpaceX Quite some other companies trying the same went under recently.
- alexpil 6y ago
  starlink latency could be faster than shortwave, once full gen2 constellation launches, and if starlink decides to care about this industry. ...disclosure: i'm the first one to build NY-Chi microwave, and Chi-Lon shortwave.
  - modeless 6y ago
    Cool! How do you figure? Doesn't shortwave take the great circle path, at lower altitude, making the path shorter?
    - alexpil 6y ago
      gen2 constellation is at 350km agl shortwave f-layer is at 200-400km agl depending on space weather difference is not that big
      - modeless 6y ago
        Sure, but it seems to me like the Starlink path will still be longer in almost all cases unless you're incredibly lucky and the satellites line up exactly along the path for a few seconds. And Starlink could have additional delays related to routing and possibly TDMA. What kind of latency issues need to be considered with shortwave?
        alexpil 6y ago
        a single orbital plane at 53' contains 7028 satellites (out of 40k total, but let's take one orbital plane) basic math, "satellite density" or "average distance between satellites" if they were just at random position is ~200km (napkin math, might be off).
        sargun 6y ago
        Some folks wrote a paper based on the proposed constellation: https://dl.acm.org/doi/10.1145/3286062.3286075 https://dl.acm.org/doi/10.1145/3286062.3286075 The paper actually talks about trading: > Already there are new private microwave relay links between New York and Chicago[11], London and Frankfurt[1], and London and Paris. These links have relatively low capacity compared to fiber, but are of high enough value to the finance industry to be worth building new low latency links In their paper, they say NYC / LON RTT will be between 58 and 66 ms -- this isn't much better than fiber. On the other hand, London to Joburg -- starlink has an advantage.
oh_sigh 6y ago
What happens in the global market if a single person consistently has a timing advantage over every other participant(because the barrier to building a global satellite network is too high/costly for anyone else)? Could Elon come to own the entire market, or is there some limit to the powers of arbitrage?
- logicchains 6y ago
  If a single player was capturing the entire arbitrage market, they'd be earning enough to justify other players building their own satellite network to capture a piece of the pie.
  - sargun 6y ago
    HFT firms make a lot of money...but space launch is even more costly. :(
- alexpil 6y ago
  it'd be rather interestink. but shortwave will be competitive with spacex, although at, of course, lower capacities. for inter-market trading, sub-ms latency differences don't matter that much.

by sargun 6y ago

ncmncm 6y ago

Starlink might get as much for denying access to specific other parties as for selling access in the first place.

modeless 6y ago

Starlink latency would be worse than shortwave. The advantage would be bandwidth, but I doubt that high bandwidth is really helpful for this application, especially if you have to give up a tiny bit of latency for it. After all, you can already have all the bandwidth you want with only slightly higher latency.

hef19898 6y ago
If memory works well, they have dedicated glass fibre for bandwidth, at least between Chicago and NY. Took the closest possible distance. Microwave is used for speed, in addition, to get binary signals from A to B. I heard that theory more than once about Starlink, it just doesn't make that much sense to me. Starlink could also be, of course, a clever way of getting a) enough launches to make reusable rockets financially feasible and/or b) getting financing for SpaceX Quite some other companies trying the same went under recently.
alexpil 6y ago
starlink latency could be faster than shortwave, once full gen2 constellation launches, and if starlink decides to care about this industry. ...disclosure: i'm the first one to build NY-Chi microwave, and Chi-Lon shortwave.
- modeless 6y ago
  Cool! How do you figure? Doesn't shortwave take the great circle path, at lower altitude, making the path shorter?
  - alexpil 6y ago
    gen2 constellation is at 350km agl shortwave f-layer is at 200-400km agl depending on space weather difference is not that big
    - modeless 6y ago
      Sure, but it seems to me like the Starlink path will still be longer in almost all cases unless you're incredibly lucky and the satellites line up exactly along the path for a few seconds. And Starlink could have additional delays related to routing and possibly TDMA. What kind of latency issues need to be considered with shortwave?
      - alexpil 6y ago
        a single orbital plane at 53' contains 7028 satellites (out of 40k total, but let's take one orbital plane) basic math, "satellite density" or "average distance between satellites" if they were just at random position is ~200km (napkin math, might be off).
        sargun 6y ago
        Some folks wrote a paper based on the proposed constellation: https://dl.acm.org/doi/10.1145/3286062.3286075 https://dl.acm.org/doi/10.1145/3286062.3286075 The paper actually talks about trading: > Already there are new private microwave relay links between New York and Chicago[11], London and Frankfurt[1], and London and Paris. These links have relatively low capacity compared to fiber, but are of high enough value to the finance industry to be worth building new low latency links In their paper, they say NYC / LON RTT will be between 58 and 66 ms -- this isn't much better than fiber. On the other hand, London to Joburg -- starlink has an advantage.

oh_sigh 6y ago

What happens in the global market if a single person consistently has a timing advantage over every other participant(because the barrier to building a global satellite network is too high/costly for anyone else)? Could Elon come to own the entire market, or is there some limit to the powers of arbitrage?

logicchains 6y ago
If a single player was capturing the entire arbitrage market, they'd be earning enough to justify other players building their own satellite network to capture a piece of the pie.
- sargun 6y ago
  HFT firms make a lot of money...but space launch is even more costly. :(
alexpil 6y ago
it'd be rather interestink. but shortwave will be competitive with spacex, although at, of course, lower capacities. for inter-market trading, sub-ms latency differences don't matter that much.