6 ms·
Isn't this sort of still the case in HFT, where some firms try building e.g. their own microwave radio tower networks to beat others by a few milliseconds?
by bschne 6y ago
Isn't this sort of still the case in HFT, where some firms try building e.g. their own microwave radio tower networks to beat others by a few milliseconds?
- Qworg 6y agoYes - between Chicago and NYC.
- hangonhn 6y agoA possible use for SpaceX's Starlink as well. Starlink doesn't have to follow the curvature of the earth so over long enough of a distance it is actually shorter and quicker to use Starlink.
- Ekaros 6y agoDon't you actually want to be as close to curvature of earth as you can? Or actually even under it. Straight line through the planet or crust would be the optimal route. Any distance you go up is making it longer than curvature.
- hangonhn 6y agoRight, so if you can't go through the crust then going up would be another option. Over long enough of a distance, say NYC to London (or even farther), the overhead of going up first and then a "straight" line horizontally (it's not completely straight because it has relay between the satellites via LOS laser but each arc would be fairly long) and back down would be shorter than a line following the curvature. (Edited: This is wrong. I had conflated the lower latency with shorter distance as others have pointed out.) BTW, I want to give full credit to my source: https://www.youtube.com/watch?v=giQ8xEWjnBs https://www.youtube.com/watch?v=giQ8xEWjnBs It also does a much better job of explaining it than I have but it is a convincing argument for how Starlink can be useful and why traders would be willing to pay a lot for it.
- scott31 6y ago> Over long enough of a distance, say NYC to London (or even farther), the overhead of going up first and then a "straight" line horizontally (it's not completely straight because it has relay between the satellites via LOS laser but each arc would be fairly long) and back down would be shorter than a line following the curvature. That is nonsense, the route is longer. You are confusing stuff, light travels faster in air compared to fiberoptic cable, so the latency will be lower, but distance is actually longer.
- deleted 6y ago[deleted]
- 0xffff2 6y agoI think GP is confusing things a bit. Starlink can actually be faster, but it's because laser links in a vacuum are on the order of 1/3 faster than terrestrial fiber optics. The distance is longer, but the information travels faster by a large enough margin to overcome the distance and result in overall lower latency.
- ineedasername 6y agoUnder ideal circumstances Starlink is claiming a 15-20ms ping. That's already too high for HFT. Also they're only orbiting about 200 miles above Earth, so unless you're already relatively close to your target location, you'll need to bounce your traffic across a whole bunch of satellites, each adding a fractions of a ms just for hardware processing + light speed to the next hop. In fact over any sufficiently long distance, doing this will actually resemble a longer curved arc circumscribing the arc of the Earth. People who really need those extra few ms have little choice but to stick to the ground, near the exchange.
- retzkek 6y agoOr shortwave between the US and Europe https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-trading-part-i-the-west-chicago-tower-mystery/ https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-tr... (I recommend reading the whole series, it's fascinating!)
- dang 6y agoLots of discussion too: https://hn.algolia.com/?query=comments%3E0%20sniperinmahwah.wordpress.com&&sort=byDate&dateRange=all&type=story&prefix https://hn.algolia.com/?query=comments%3E0%20sniperinmahwah....
- dahfizz 6y agoNit: the microwave networks themselves are a standard feature of a lot of exchanges, such as SIX and CME. There is some posturing between companies building receivers that you may have heard about[1], but that is largely because companies are building towers so close they are causing interference. The tower location does not have much of an effect on latency because the microwave network in this case always terminates at NYSE. If you build your microwave tower a few feet closer to the transmitter (Chicago), then you have to run a few more feet of cable to the colo. [1] https://www.bloomberg.com/news/features/2019-03-08/the-gazillion-dollar-standoff-over-two-high-frequency-trading-towers https://www.bloomberg.com/news/features/2019-03-08/the-gazil...
- amelius 6y agoYeah, it's okay if stock traders do it. But if Amazon drivers do it, ...
- _e 6y agoYes, but it is microseconds.... not milliseconds.
- smabie 6y agoThat's only if you're arbitraging between multiple exchanges at physically different locations. If you're just interested in having low latency to one market, you just pay the colo fee.