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Comment by earlz | Hacker News Reader

The bad thing about satellite that makes it unsuitable for many use cases will always remain to be latency, not speed or availability. 1.5 second ping is perfectly usable for web browsing, but it is painful for many other workflows.. And there's no current way with our technology we can "fix" this problem. It boils down to speed of light issues.

I for one am still hoping we'll eventually get quantum internet that goes through the earth rather than around it.

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Musk is planning to put satellites in LEO, which gives you a roundtrip of 1 to 12 milliseconds (just light; not counting data processing), depending on placement. The 1.5 second ping exist only for current Internet satellites that are parked in GEO.

There's a tradeoff there in the number of satellites needed and the amount of fuel needed to maintain their orbits... the closer to the planet, the more drag. I suspect the larger number of smaller satellites will also produce lower available bandwidth, but I'm not sure how that scales.

I recently saw an article about impulse engines using an arc-welding type approach where just electricity and some sort of metallic rod were needed. If these can be made small enough that could bring down the cost of station keeping dramatically, since presumably you could get a lot more lifetime thrust per kg of mass using that metal, then you would with propellants. (And the electricity can be harvested in orbit.)

Most geostationary orbit satellites are actually closer to 35,000 km above the surface of the planet. As stated by other commenters, LEO, where these microsats would be, is only about 2000 km above the surface. SpaceX wants to put their a mere 1200km[1] up. For most (read non-gamer) use cases, this should be extremely adequate, and it will be at a nice price point if they put up the 4000+ of these that Elon Musk wants to with SpaceX.

[1] http://www.geekwire.com/2015/photos-spacex-founder-elon-musk...

Grace Hopper explains it best: https://www.youtube.com/watch?v=JEpsKnWZrJ8

"Between here and the satellite there is a very... large... number... of nanoseconds."

"The bad thing about satellite that makes it unsuitable for many use cases will always remain to be latency, not speed or availability. 1.5 second ping is perfectly usable for web browsing, but it is painful for many other workflows."

I have Viasat Exede at my rural home that is unserved by other network products (no mobile signal, no CATV, no DSL).

Ping times are ~700ms and given my high reliance on SSH to do my work I was skeptical ... but it's not that bad.

I can't speak to gaming, etc., but for interactive login and things like skype/vonage it works OK.

What terminal are you using for SSH? Mosh? https://mosh.mit.edu/

No, just plain old terminal.app in OSX.

Or local console login on a FreeBSD server at home.

Nothing special.

Definitely check out Mosh. It's a (roughly! Don't yell at me:) layer ontop of SSH that uses the normal protocol for the initial connection, but after that it uses a UDP based protocol that is heavily tuned for poor network environments.

That, ontop of a whole host of other reasons, is why it's amazing. Absolutely love it, and have been using it every day for over a year now. Despite frequent internet drops (yay, comcast) and laptop closures, i only reconnect to the server when i reboot my laptop (maybe once a month, at best). It's neato!

edit: Note that my "server" work is my IDE (vim), and many panes of tmux, etcetc. Basically all my work. So it's used over 50h a week.

Low orbit satellites will have much lower ping than 1.5 second. 5000km compared to 20000 km and more

That would be interesting, I think it'd still end up being a bit too much for anything interactive, but would be much closer to usable

Not really no. LEO is 160-2000km up; it takes light from 1 to 12 milliseconds to do a roundtrip there. This is an order of magnitude faster than it takes your phone or tablet to react to touch input. It'll be more than enough for interactive things.

Add to this that most terrestrial networking is done over fiber optics - the speed of light through the glass is about 2/3 the speed of light in a vacuum. If you're transmitting radio waves into space and between satellites, you'd be as fast as most terrestrial networks so long as the transmitted arc plus twice the altitude was less than 1.5 times the same arc at ground level.

As an aside, the lower speed of light through fiber optic cable is one reason many stock trading platforms use line-of-sight microwave for their primary transmission. For HFT, those uS (and even nS) matter.

In the US, most satellite internet providers also have data caps. ~$50/10GB/month around me, and each additional GB/month is $10.

That's exactly right. The main complaint I have with satellite isn't the latency or speed. Although the latency is awful.

It's that 15GB costs ~$100 and comes with an automatic next throttle on next month's bandwidth if I go over. Or, purchase additional GB for $10 each.

It's like having a Porsche with a thimble sized tank of gasoline.

Yep, I have a friend who pays $150/month for 50mbit/s satellite with a 20G data cap. He makes heavy use of the unmetered time from 12am-4am though. And yea, I did some look ups before about this issue and it's ridiculous the cap structure some of these providers have, like this bit from Wild Blue:

> After exceeding either of the usage thresholds, which vary by service package, we may significantly slow and/or restrict your service, or certain uses of your service. Your full service will be restored when your data usage in the prior 30 days falls below 70% for both usage thresholds.

So, if you go over, then for the next 30 days you're throttled UNTIL your volume stays under 70% of your cap over a 30 day period... Like, how is it even legal to sell one thing, but punish for using more than 70% of it sometimes

They have sold 100k Porsches on to an information superhighway that has only room for 1000 at a time so they only let each one use it for a relatively short amount of time each month. i.e the do contention management over a month.

Most providers sell consumer broadband access based on headline speed because that's what the fixed line providers do.

When buying "professional" satellite broadband; users can buy un-contented at much lower speeds. A Ford Transit with a dedicated lane perhaps...

For standard web stuff HTTP2 should make a difference for people with high latencies, possibly some kind of converting proxy might help for legacy sites too.

I'm using sattelite internet from Cambodia (WiMax). Ping to 8.8.8.8 is around 8ms, and I pay $25 a month for 4mbit. Relability is better than the ADSL or Fiber options over here, due to countries like these being absolutely horrible at wiring cables.

WiMAX is not delivered over satellites, it uses ground-based basestations.

The lowest latency satellite systems, using LEO orbit satellites, are around 40ms roundtrip.

I stand corrected -- after some Googling, I now realize it's more like 4G/LTE than anything else. Thanks for clearing that up!

Are you sure it's really going through a satellite? WiMAX isn't per se satellite technology but normal radio with fixed basestations (though satellites are sometimes used to link really remote WiMAX stations)

also I have seen 8.8.8.8 respond from cache kind (don't know how it works) 8ms seems to be impossible from combodia even on wired unless local ISP end is responding to that

I believe Google is using anycast for their DNS servers. Basically, the device responding to his ping from Cambodia likely isn't very far away.

https://en.wikipedia.org/wiki/Anycast

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