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From the FCC quote in the article: "Propagation delay in a satellite network does not alone account for latency in other parts of the network such as processing
by T-A 6y ago
From the FCC quote in the article: "Propagation delay in a satellite network does not alone account for latency in other parts of the network such as processing, routing, and transporting traffic to its destination."
In other words, client and server are not both sitting right under the same satellite. The trip to and from LEO is just part of the full route; you also have server to ground station and (in future) uplink satellite to downlink satellite (AFAIK Starlink currently doesn't do that).
- messe 6y agoIs there any public documentation on how much of the round-trip time the processing and routing takes up? It has had the shit optimized out of it every else, so I can't imagine it would get significantly worse for a satellite, especially one of SpaceX's which attempt to use commodity hardware as much as possible.
- wtracy 6y agoSatellites have to operate in a very different thermal and radiation environment than most networking hardware. Cooling is very difficult when you're surrounded by a vacuum. Also, without the planet acting as a heat sink, the difference between daytime and nighttime temperatures is staggering. I don't actually know to what extent radiation hardening is a concern for these satellites. They're well below the Van Allen Belt, so the background radiation is nothing like deep space. Still, it's something you need to consider for systems that are expected to have years of continuous uptime. (The Russians use commodity PC hardware on the ISS for systems not involved in navigation or life support. But that's a situation where there are people around to hit the power button.) Not to mention that replacing hardware is expensive, and repair is basically impossible, so there are incentives to prioritize reliability over performance.
- TeMPOraL 6y ago> Not to mention that replacing hardware is expensive, and repair is basically impossible, so there are incentives to prioritize reliability over performance. SpaceX is actually changing this equation quite a bit in case of Starlink - mass-produced satellites + much cheaper and more frequent launches = replacing hardware gets much cheaper, which means they can prioritize performance over reliability more than it's customary in the industry.
- messe 6y ago> Not to mention that replacing hardware is expensive, and repair is basically impossible, so there are incentives to prioritize reliability over performance. I'm well aware. But SpaceX is heading in the direction of quantity over quality, and banking on the sheer volume of satellites being launched cheaply outweighing any one failure.
- nwallin 6y agoI mean- sure? But that's also true of terrestrial internet. It's 22 hops between my laptop and www.google.com, and it pings at 5-10ms. Certainly Starlink isn't do any fancy routing that my internet isn't already doing?
- stefan_ 6y agoSwitches and fiber are well known proven technology. Satellite laser interlinks are R&D dreams at the moment.
- cameldrv 6y agoThere are satellite laser interlinks in orbit right now.
- portillo 6y agoSure, operated manually by a bunch of people with PhDs.
- GoOnThenDoTell 6y agoI thought the current starlink generation wasn’t using laser links yet
- Rebelgecko 6y agoI believe both your comment and the parent comment are true. Laser comm has been done at fairly high speeds (both sat to sat and sat to ground station), but it's relatively cutting edge and Starlink isn't currently doing it