Satellite internet is awfully slow for interactive use
Posted by jpluimers on 2018/09/17
A while back, Thomas Mueller assumed that Satellite internet could be an alternative for rural areas in Germany: [WayBack] > Auch der Internet-Anschluss über Satellit funktioniere allenfalls quälend langsam <Das kommt mir aber ziemlich seltsam vor… – Thomas Mueller (dummzeuch) – Google+ as a response to [Archive.is] Telekom-Posse: Wirt soll eine Million Euro für schnelles Internet zahlen – WELT.
So I summed up what throttling to 600 (optimistic) or 1000 millisecond (realistic) latency on a 10 megabit connection means: awfully slow for interactive use.
The problem with satellite based internet is latency times: 500 milliseconds is the physical minimum for a geostationary connection. It can easily double with overbooked connections (default with consumer DSL/Cable/Fiber).
The latency combined with the very chatty nature of most applications, is the real killer for your experience.
Compare that to my speeds 2 years ago: https://wiert.me/2015/10/05/fiber-to-fiber-speed-beats-cable-to-fiber-speed-by-a-factor-2-all-three-internet-connections-are-in-the-same-house/
I just did a comparison with the fiber connection at my brother (who lives some 20 miles away) and work too and re-checked the fiber connections in the article (they stayed the same).
- fiber 1 = home
- fiber 2 = home
- fiber 3 = brother
- fiber 4 = work
Traceroute results:
- fiber 1 to fiber 2: 5 milliseconds
- fiber 3 to fiber 2: 8 milliseconds
- fiber 4 to fiber 2: 4 milliseconds
- cable to fiber 2: 10 millseconds
- ADSL to fiber 2: 15 millseconds
With these, you can have > 50 connections per second.
Satellite gives you 2 connections per second if you are lucky.
The blog page takes ~160 web requests.
- DOM content load ~ 1.0 seconds
- Full load finished ~2.2 seconds
- Render finished ~5.0 seconds
I throttled it down to Satellite speed:
- 10 megabit downstream
- 2 megabit upstream
- 600 millisecond latency
Now this is the load:
- DOM content load ~ 2.9 seconds
- Full load finished ~9.9 seconds
- Render finished ~10.0 seconds
Increasing the latency to 1000 milliseconds brings this:
- DOM content load ~ 4.2 seconds
- Full load finished ~11.8 seconds
- Render finished ~14.9 seconds
Fully loading gmail.com or booking .com with 1000 millisecond latency takes over 30 seconds.
References:
–jeroen
Source: Satellite Internet faster than advertised, but latency still awful | Ars Technica
The Wiert Corner - irregular stream of stuff 
Thomas Mueller said
What I meant was that Satellite Internet is either slow or fast. It doesn’t matter whether the user is located in a rural area or somewhere in a large city.
jpluimers said
Thanks for explaining that in more detail.