xplornet contact or any experience with their satellite service?
Mel Beckman
mel at beckman.org
Tue Apr 21 14:05:20 UTC 2020
Brian,
Satellite services are shared bandwidth broadcast systems. The behavior you’re seeing is pretty common at times when you’re competing for access with other users. Just like the regular Internet, there are times of day when people tend to move more data, and because of latency and other limitations on bidirectional traffic, packets get delivered in batches. It’s not possible to interleave bytes, or even packets themselves.
So when you see low or no throughput, it’s because the transponder is addressing packets to other users.
-mel beckman
> On Apr 21, 2020, at 6:53 AM, Brian J. Murrell <brian at interlinx.bc.ca> wrote:
>
> A friend of mine just recently got Xplornet satellite service at his
> rural home. I'm well aware of the latency issues with satellite
> although frankly his latency is much better than I had feared it would
> be and is around 600-700ms.
>
> But what seems to be worse than the latency is the "burstiness" of the
> traffic and I am just wondering if that is normal/expected for
> satellite service in general, and/or expected from Xplornet's service,
> or if what I am seeing is not expected at all (i.e. not an artifact of
> the satellite signal but rather a network management issue).
>
> Here's iperf3 for 30 seconds sending data (i.e. upload speed):
>
> [ ID] Interval Transfer Bitrate
> [ 5] 0.00-1.21 sec 12.9 KBytes 87.4 Kbits/sec
> [ 5] 1.21-2.00 sec 6.47 KBytes 67.2 Kbits/sec
> [ 5] 2.00-3.00 sec 22.0 KBytes 180 Kbits/sec
> [ 5] 3.00-4.00 sec 41.4 KBytes 339 Kbits/sec
> [ 5] 4.00-5.00 sec 41.4 KBytes 339 Kbits/sec
> [ 5] 5.00-6.00 sec 55.6 KBytes 456 Kbits/sec
> [ 5] 6.00-7.00 sec 69.9 KBytes 572 Kbits/sec
> [ 5] 7.00-8.00 sec 89.3 KBytes 731 Kbits/sec
> [ 5] 8.00-9.00 sec 120 KBytes 986 Kbits/sec
> [ 5] 9.00-10.00 sec 86.7 KBytes 710 Kbits/sec
> [ 5] 10.00-11.00 sec 133 KBytes 1.09 Mbits/sec
> [ 5] 11.00-12.00 sec 184 KBytes 1.51 Mbits/sec
> [ 5] 12.00-13.00 sec 186 KBytes 1.53 Mbits/sec
> [ 5] 13.00-14.00 sec 159 KBytes 1.30 Mbits/sec
> [ 5] 14.00-15.00 sec 0.00 Bytes 0.00 bits/sec
> [ 5] 15.00-16.00 sec 0.00 Bytes 0.00 bits/sec
> [ 5] 16.00-17.00 sec 93.2 KBytes 763 Kbits/sec
> [ 5] 17.00-18.00 sec 264 KBytes 2.16 Mbits/sec
> [ 5] 18.00-19.00 sec 124 KBytes 1.02 Mbits/sec
> [ 5] 19.00-20.00 sec 157 KBytes 1.28 Mbits/sec
> [ 5] 20.00-21.00 sec 120 KBytes 986 Kbits/sec
> [ 5] 21.00-22.00 sec 86.7 KBytes 710 Kbits/sec
> [ 5] 22.00-23.00 sec 369 KBytes 3.02 Mbits/sec
> [ 5] 23.00-24.00 sec 197 KBytes 1.61 Mbits/sec
> [ 5] 24.00-25.00 sec 90.6 KBytes 741 Kbits/sec
> [ 5] 25.00-26.00 sec 193 KBytes 1.58 Mbits/sec
> [ 5] 26.00-27.00 sec 192 KBytes 1.57 Mbits/sec
> [ 5] 27.00-28.00 sec 189 KBytes 1.55 Mbits/sec
> [ 5] 28.00-29.00 sec 193 KBytes 1.58 Mbits/sec
> [ 5] 29.00-30.00 sec 179 KBytes 1.46 Mbits/sec
> - - - - - - - - - - - - - - - - - - - - - - - - -
> [ ID] Interval Transfer Bitrate Retr
> [ 5] 0.00-32.20 sec 4.41 MBytes 1.15 Mbits/sec 388 sender
> [ 5] 0.00-30.00 sec 3.57 MBytes 998 Kbits/sec receiver
>
> which averaged the overall prescribed "upload" speed, but notice that
> it's not 1Mb/s in any kind of a steady stream but rather bursts of
> higher than 1Mb/s speed followed by low/no speed. At one point it was
> 2 seconds with no transfer at all even.
>
> and here's receiving (i.e. "download"):
>
> [ ID] Interval Transfer Bitrate Retr Cwnd
> [ 5] 0.00-1.35 sec 46.6 KBytes 283 Kbits/sec 0 12.9 KBytes
> [ 5] 1.35-2.00 sec 0.00 Bytes 0.00 bits/sec 0 12.9 KBytes
> [ 5] 2.00-3.00 sec 67.3 KBytes 551 Kbits/sec 0 37.5 KBytes
> [ 5] 3.00-4.00 sec 46.6 KBytes 382 Kbits/sec 0 40.1 KBytes
> [ 5] 4.00-5.00 sec 105 KBytes 858 Kbits/sec 0 44.0 KBytes
> [ 5] 5.00-6.00 sec 88.0 KBytes 721 Kbits/sec 0 54.3 KBytes
> [ 5] 6.00-7.00 sec 141 KBytes 1.16 Mbits/sec 0 69.9 KBytes
> [ 5] 7.00-8.00 sec 124 KBytes 1.02 Mbits/sec 0 101 KBytes
> [ 5] 8.00-9.00 sec 186 KBytes 1.53 Mbits/sec 0 146 KBytes
> [ 5] 9.00-10.00 sec 248 KBytes 2.04 Mbits/sec 0 206 KBytes
> [ 5] 10.00-11.00 sec 311 KBytes 2.54 Mbits/sec 0 257 KBytes
> [ 5] 11.00-12.00 sec 0.00 Bytes 0.00 bits/sec 43 194 KBytes
> [ 5] 12.00-13.00 sec 0.00 Bytes 0.00 bits/sec 75 199 KBytes
> [ 5] 13.00-14.00 sec 435 KBytes 3.56 Mbits/sec 0 199 KBytes
> [ 5] 14.00-15.00 sec 0.00 Bytes 0.00 bits/sec 34 114 KBytes
> [ 5] 15.00-16.00 sec 0.00 Bytes 0.00 bits/sec 34 140 KBytes
> [ 5] 16.00-17.00 sec 373 KBytes 3.05 Mbits/sec 0 149 KBytes
> [ 5] 17.00-18.00 sec 0.00 Bytes 0.00 bits/sec 0 162 KBytes
> [ 5] 18.00-19.00 sec 373 KBytes 3.05 Mbits/sec 0 168 KBytes
> [ 5] 19.00-20.00 sec 0.00 Bytes 0.00 bits/sec 0 171 KBytes
> [ 5] 20.00-21.00 sec 373 KBytes 3.05 Mbits/sec 0 172 KBytes
> [ 5] 21.00-22.00 sec 0.00 Bytes 0.00 bits/sec 14 141 KBytes
> [ 5] 22.00-23.00 sec 0.00 Bytes 0.00 bits/sec 0 120 KBytes
> [ 5] 23.00-24.00 sec 373 KBytes 3.05 Mbits/sec 0 131 KBytes
> [ 5] 24.00-25.00 sec 0.00 Bytes 0.00 bits/sec 1 146 KBytes
> [ 5] 25.00-26.00 sec 0.00 Bytes 0.00 bits/sec 14 104 KBytes
> [ 5] 26.00-27.00 sec 0.00 Bytes 0.00 bits/sec 0 104 KBytes
> [ 5] 27.00-28.00 sec 373 KBytes 3.05 Mbits/sec 0 107 KBytes
> [ 5] 28.00-29.00 sec 0.00 Bytes 0.00 bits/sec 0 119 KBytes
> [ 5] 29.00-30.00 sec 373 KBytes 3.05 Mbits/sec 0 123 KBytes
> - - - - - - - - - - - - - - - - - - - - - - - - -
> [ ID] Interval Transfer Bitrate Retr
> [ 5] 0.00-30.00 sec 3.94 MBytes 1.10 Mbits/sec 215 sender
> [ 5] 0.00-30.80 sec 3.13 MBytes 853 Kbits/sec receiver
>
> Again, very bursty with periods of 1-2 seconds with no transfer.
>
> As you can imagine, the bursiness of this makes for horrible video
> conferencing since that cannot "buffer" the way single-direction
> streams like streaming video can and the codec ends up using the "worst
> case" dips as the speed of the connection and encodes for that.
>
> Cheers,
> b.
>
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