Forum Discussion

Cblucas3's avatar
Cblucas3
Freshman
7 years ago

Latency Or Satellite Shortcomings?

There is all this talk of distance affecting latency which doesn't seem to wash. If the signal has to travel 88,000 miles latency shouldn't be an issue when the speed of light is considered. Traveling...
Performance
maratsade's avatar
maratsade
Distinguished Professor IV
7 years ago

It seems the OP doesn't want any help unless it corroborates his incorrect assumptions, so it seems this thread should perhaps be closed. Mods?

 

MarkJFine wrote:

Speed of light is not instantaneous, it's roughly 186,282 mi/sec. If the ground station is in San Diego, round trip for me in Virginia is roughly 97,462 miles. Simple math: 97,462 / 186,282  = 0.523 sec (or 523 mSec).

 

This is just for the four legs of the radio path of a 20GHz signal (me->sat->gs and back to me), which does not include any processing time at the satellite or internal to the ground station (roughly 75mS), nor any additonal latency between the ground station through it's provider on the terrestrial internet.

 

Should add that a traceroute shows all of this in real time.

Cblucas3's avatar
Cblucas3
Freshman
7 years ago
I appreciate the your post. It further shows that distance is not an issue with latency. Not at these insignificant amounts relative to the speed of light.
You stated that it is roughly 186,282 mi/s. I must say you are right on with it being exactly 186282.397051 mi/s.
Would you have any thoughts on my latency problem. I think that maybe I didn't emphasize that my latency is out of range for what is expected with satellite service. I cannot even get on Facebook 75% of the time on average. It will tell me there is no connection. After several attempts with the Retry link it will finally connect. However most of the time I just resort to my mobile data
It's especially disconcerting when a significant amount of time is spent on a form or typing a large amount of characters in a forum such as this and to lose it all because of a time out and Form Resubmission command. I've learned to to copy said text so I can do a paste if I'm on Hughsnet.
  • MarkJFine's avatar
    MarkJFine
    Professor
    7 years ago
    Cblucas3 wrote:
    You stated that it is roughly 186,282 mi/s. I must say you are right on with it being exactly 186282.397051 mi/s.

    I'm a radio engineer by trade. These are basics.

     

    Cblucas3 wrote:
    Would you have any thoughts on my latency problem.

    As I mentioned in the same post and previously, I can't determine where the latency problem exists without seeing a traceroute to whatever site you're trying to get to. It could be inside the HughesNet gateway, it could be at the gateway's provider (more than likely), it could be anywhere in the route between the provider and the site you're trying to get to.

     

    Nobody can do this for you, and it's as simple as opening up a command window in Windows and typing something like:
      tracert microsoft.com