5 ms·

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 perfec

by earlz 11y ago

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.

vasili111 11y ago
Low orbit satellites will have much lower ping than 1.5 second. 5000km compared to 20000 km and more
- earlz 11y ago
  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
  - TeMPOraL 11y ago
    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.
    - smoyer 11y ago
      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.
stingraycharles 11y ago
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.
- throwaway7767 11y ago
  WiMAX is not delivered over satellites, it uses ground-based basestations. The lowest latency satellite systems, using LEO orbit satellites, are around 40ms roundtrip.
  - stingraycharles 11y ago
    I stand corrected -- after some Googling, I now realize it's more like 4G/LTE than anything else. Thanks for clearing that up!
- chkuendig 11y ago
  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)
- deleted 11y ago
  [deleted]
- jsudhams 11y ago
  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
  - sathackr 11y ago
    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 https://en.wikipedia.org/wiki/Anycast
bsilvereagle 11y ago
In the US, most satellite internet providers also have data caps. ~$50/10GB/month around me, and each additional GB/month is $10.
- Loughla 11y ago
  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.
  - earlz 11y ago
    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
  - A_Beer_Clinked 11y ago
    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...
stewartbutler 11y ago
Grace Hopper explains it best: https://www.youtube.com/watch?v=JEpsKnWZrJ8 https://www.youtube.com/watch?v=JEpsKnWZrJ8 "Between here and the satellite there is a very... large... number... of nanoseconds."
SEJeff 11y ago
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-unveils-new-10b-space-internet-plan-private-seattle-event/ http://www.geekwire.com/2015/photos-spacex-founder-elon-musk...
TeMPOraL 11y ago
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.
- MCRed 11y ago
  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.)
rsync 11y ago
"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.
- blazespin 11y ago
  What terminal are you using for SSH? Mosh? https://mosh.mit.edu/ https://mosh.mit.edu/
  - rsync 11y ago
    No, just plain old terminal.app in OSX. Or local console login on a FreeBSD server at home. Nothing special.
    - fizzbatter 11y ago
      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.
ZeroGravitas 11y ago
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.

by earlz 11y ago

vasili111 11y ago

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

earlz 11y ago
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
- TeMPOraL 11y ago
  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.
  - smoyer 11y ago
    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.

stingraycharles 11y ago

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.

throwaway7767 11y ago
WiMAX is not delivered over satellites, it uses ground-based basestations. The lowest latency satellite systems, using LEO orbit satellites, are around 40ms roundtrip.
- stingraycharles 11y ago
  I stand corrected -- after some Googling, I now realize it's more like 4G/LTE than anything else. Thanks for clearing that up!
chkuendig 11y ago
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)
deleted 11y ago
[deleted]
jsudhams 11y ago
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
- sathackr 11y ago
  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 https://en.wikipedia.org/wiki/Anycast

bsilvereagle 11y ago

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

Loughla 11y ago
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.
- earlz 11y ago
  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
- A_Beer_Clinked 11y ago
  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...

stewartbutler 11y ago

Grace Hopper explains it best: https://www.youtube.com/watch?v=JEpsKnWZrJ8 https://www.youtube.com/watch?v=JEpsKnWZrJ8 "Between here and the satellite there is a very... large... number... of nanoseconds."

SEJeff 11y ago

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-unveils-new-10b-space-internet-plan-private-seattle-event/ http://www.geekwire.com/2015/photos-spacex-founder-elon-musk...

TeMPOraL 11y ago

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.

MCRed 11y ago
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.)

rsync 11y ago

"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.

blazespin 11y ago
What terminal are you using for SSH? Mosh? https://mosh.mit.edu/ https://mosh.mit.edu/
- rsync 11y ago
  No, just plain old terminal.app in OSX. Or local console login on a FreeBSD server at home. Nothing special.
  - fizzbatter 11y ago
    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.

ZeroGravitas 11y ago

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.