Elon should really do a John Henry if he can afford to set it up. Run a head-to-head data-transmission with checksum validation in some theatrical setting. For bonus points he could (if it's possible) run a self-driving car demo where the computation is being done and relaid by a LEO uplink.
Also, I hear what you're saying but... Right now the Algorithmic traders all use fiber and new fiber is constantly being rolled out to support even lower latency connections so I'm skeptical - if it was competitive wouldn't G&S be using it to contact the London stock exchange? Or, is it that fiber can produce lower latency in idyllic scenarios but that congestion pushes the latency beyond that accomplishable by an LEO setup for us plebs?
> if it was competitive, wouldn't G&S be using it to contact the London stock exchange?
They will, but no such satellite network currently exists. Right now, all of the satellite internet services are using satellites in high orbits. That means they can cover more of the Earth's surface per-satellite, and the satellites last a long time. This was necessary when rocket launches cost >$10,000/kg.
SpaceX is drastically lowering the prices of launching satellites ($1k-$2k/kg, Starship will probably be <$500/kg), and they are taking advantage of that by launching thousands of satellites into LEO (Low Earth Orbit). These satellites will have a 5-7 year service life, which will reduce the cost per satellite and allow for regular upgrades via replacement.
Newer hardware and lower altitudes means less latency and more bandwidth than previous satellites. It will definitely beat transatlantic fiber on latency, but bandwidth will be more limited.
I remember reading about line-of-sight microwave links being used for trading here on HN. I think line of sight is the key difference between fiber and radio.
I dont know if I'd call it direct line of site, but low bandwidth directional microwave communication is definitely used over-the-horizon from say Chicago to London. This [1] Bloomberg article has a great rundown on microwave in finance.
Bandwidth is low, but latency beats fibre, and you can bounce microwave off the ionosphere between London and Chicago (and various other routes). This article doesn't mention the cross Atlantic transmissions, but it is possible, and does happen.
Disclosure: I have worked at several of the Chicago based firms mentioned in the linked Bloomberg article.
Edit: grammar, formatting.
I wasnt directly involved in any of the microwave networking, but ask me what you want and I'll answer to the best of my ability.
As far as I'm aware, there aren't any LEO satellite internet providers at the moment (a few in GSO, but the latency there is probably too long to make it relevant for trading), so I think that it just isn't an option. It'll be interesting to see what happens when the first LEO constellations come online.
Serious algorithmic traders use point-to-point microwave links, because the speed of radio waves in air is about 50% faster than light in a glass fiber.
The majority of the latency improvment from these hft networks is because the path taken by them is more direct. Fiber routes follow roads and railroad tracks. The series of point to point antennas takes closer to a straight line.
Also, I hear what you're saying but... Right now the Algorithmic traders all use fiber and new fiber is constantly being rolled out to support even lower latency connections so I'm skeptical - if it was competitive wouldn't G&S be using it to contact the London stock exchange? Or, is it that fiber can produce lower latency in idyllic scenarios but that congestion pushes the latency beyond that accomplishable by an LEO setup for us plebs?