NTPsec

b-ntpsec-7-day-stats

Report generated: Fri May 29 06:04:35 2020 UTC
Start Time: Fri May 22 06:04:23 2020 UTC
End Time: Fri May 29 06:04:23 2020 UTC
Report published: Thu May 28 23:05:10 2020 PDT
Report Period: 7.0 days

Local Clock Time/Frequency Offsets

local offset plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Time Offset -13.620 -1.369 -1.056 0.023 1.070 1.351 2.370 2.126 2.720 0.756 0.006 µs -5.937 44.24
Local Clock Frequency Offset -6.445 -6.426 -6.240 -5.715 -5.457 -5.423 -5.418 0.782 1.003 0.249 -5.782 ppm -1.429e+04 3.48e+05

The time and frequency offsets between the ntpd calculated time and the local system clock. Showing frequency offset (red, in parts per million, scale on right) and the time offset (blue, in μs, scale on left). Quick changes in time offset will lead to larger frequency offsets.

These are fields 3 (time) and 4 (frequency) from the loopstats log file.



Local RMS Time Jitter

local jitter plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local RMS Time Jitter 93.000 151.000 177.000 263.000 390.000 470.000 3,273.000 213.000 319.000 104.216 274.496 ns 21.44 364

The RMS Jitter of the local clock offset. In other words, how fast the local clock offset is changing.

Lower is better. An ideal system would be a horizontal line at 0μs.

RMS jitter is field 5 in the loopstats log file.



Local RMS Frequency Jitter

local stability plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local RMS Frequency Jitter 22.000 40.000 54.000 177.000 378.000 491.000 4,214.000 324.000 451.000 152.799 194.756 10e-12 12.17 248.2

The RMS Frequency Jitter (aka wander) of the local clock's frequency. In other words, how fast the local clock changes frequency.

Lower is better. An ideal clock would be a horizontal line at 0ppm.

RMS Frequency Jitter is field 6 in the loopstats log file.



Local Clock Time Offset Histogram

local offset histogram plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Offset -13.620 -1.369 -1.056 0.023 1.070 1.351 2.370 2.126 2.720 0.756 0.006 µs -5.937 44.24

The clock offsets of the local clock as a histogram.

The Local Clock Offset is field 3 from the loopstats log file.



Local Temperatures

local temps plot

Local temperatures. These will be site-specific depending upon what temperature sensors you collect data from. Temperature changes affect the local clock crystal frequency and stability. The math of how temperature changes frequency is complex, and also depends on crystal aging. So there is no easy way to correct for it in software. This is the single most important component of frequency drift.

The Local Temperatures are from field 3 from the tempstats log file.



Local Frequency/Temp

local freq temps plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -6.445 -6.426 -6.240 -5.715 -5.457 -5.423 -5.418 0.782 1.003 0.249 -5.782 ppm -1.429e+04 3.48e+05
Temp ZONE0 59.072 60.148 60.148 62.838 66.604 67.142 68.218 6.456 6.994 1.823 63.079 °C

The frequency offsets and temperatures. Showing frequency offset (red, in parts per million, scale on right) and the temperatures.

These are field 4 (frequency) from the loopstats log file, and field 3 from the tempstats log file.



Local GPS

local gps plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
nSats 4.000 6.000 6.000 8.000 10.000 11.000 12.000 4.000 5.000 1.134 8.279 nSat 268.8 1814
TDOP 0.580 0.640 0.730 1.070 1.750 2.390 4.750 1.020 1.750 0.361 1.157 19.66 90.16

Local GPS. The Time Dilution of Precision (TDOP) is plotted in blue. The number of visible satellites (nSat) is plotted in red.

TDOP is field 3, and nSats is field 4, from the gpsd log file. The gpsd log file is created by the ntploggps program.

TDOP is a dimensionless error factor. Smaller numbers are better. TDOP ranges from 1 (ideal), 2 to 5 (good), to greater than 20 (poor). Some GNSS receivers report TDOP less than one which is theoretically impossible.



Server Offsets

peer offsets plot

The offset of all refclocks and servers. This can be useful to see if offset changes are happening in a single clock or all clocks together.

Clock Offset is field 5 in the peerstats log file.



Server Offset 104.131.155.175

peer offset 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 104.131.155.175 -0.746 1.334 1.601 2.673 3.585 3.985 15.511 1.984 2.651 0.749 2.643 ms 28.45 210.3

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 169.229.128.134

peer offset 169.229.128.134 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 169.229.128.134 0.269 2.048 2.290 2.606 3.022 3.391 4.114 0.733 1.343 0.264 2.619 ms 736.1 6802

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 178.62.68.79

peer offset 178.62.68.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 178.62.68.79 -14.817 -10.722 -5.211 3.209 12.084 15.449 18.971 17.295 26.170 5.107 3.364 ms -1.183 4.693

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 192.168.1.10

peer offset 192.168.1.10 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.10 -92.462 19.049 49.085 86.921 114.383 134.703 205.458 65.298 115.654 21.576 84.883 µs 33.15 122.6

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 203.123.48.219

peer offset 203.123.48.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 203.123.48.219 -5.815 -2.196 2.691 4.305 25.883 26.519 33.462 23.192 28.716 7.118 6.754 ms 2.073 6.169

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 204.17.205.24

peer offset 204.17.205.24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.17.205.24 1.000 1.333 1.557 1.964 2.490 2.941 3.671 0.933 1.609 0.294 1.989 ms 210.1 1332

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 216.218.192.202

peer offset 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.192.202 -1.135 2.040 2.213 2.499 2.919 3.220 4.441 0.706 1.179 0.246 2.521 ms 820.3 7850

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 216.218.254.202

peer offset 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.254.202 1.916 2.083 2.291 2.591 3.018 3.333 3.603 0.727 1.250 0.228 2.615 ms 1174 1.262e+04

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset SHM(0)

peer offset SHM(0) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(0) -438.810 -389.439 -374.306 -340.773 -294.615 -269.769 -236.037 79.691 119.670 24.098 -338.614 ms -3455 5.266e+04

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset SHM(1)

peer offset SHM(1) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(1) -13.621 -1.370 -1.057 0.024 1.071 1.352 2.371 2.128 2.722 0.757 0.006 µs -5.932 44.11

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Jitters

peer jitters plot

The RMS Jitter of all refclocks and servers. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 104.131.155.175

peer jitter 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 104.131.155.175 0.000 0.000 0.381 2.059 11.412 25.432 139.704 11.030 25.432 8.789 4.351 ms 9.684 143.9

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 169.229.128.134

peer jitter 169.229.128.134 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 169.229.128.134 0.000 0.198 0.343 2.152 10.559 18.470 136.384 10.217 18.272 7.319 4.103 ms 8.83 131.7

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 178.62.68.79

peer jitter 178.62.68.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 178.62.68.79 0.000 0.442 0.979 4.683 13.412 20.295 32.437 12.433 19.853 4.499 5.845 ms 2.845 12.26

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 192.168.1.10

peer jitter 192.168.1.10 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.10 0.005 0.012 0.022 0.142 8.721 14.394 303.554 8.699 14.382 7.133 2.130 ms 23.37 856.7

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 203.123.48.219

peer jitter 203.123.48.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 203.123.48.219 0.000 0.290 0.490 2.599 14.857 26.065 147.925 14.367 25.775 7.888 4.972 ms 9.388 164.5

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 204.17.205.24

peer jitter 204.17.205.24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.17.205.24 0.128 0.278 0.441 2.296 12.177 19.453 117.371 11.735 19.174 5.988 4.343 ms 7.644 128.5

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 216.218.192.202

peer jitter 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.192.202 0.000 0.216 0.367 1.976 9.765 17.864 141.526 9.398 17.648 6.454 3.773 ms 10.24 183.2

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 216.218.254.202

peer jitter 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.254.202 0.151 0.220 0.404 2.627 11.727 18.455 76.399 11.323 18.235 5.173 4.367 ms 5.71 72.42

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter SHM(0)

peer jitter SHM(0) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter SHM(0) 0.919 3.850 5.199 9.951 20.860 29.324 68.987 15.661 25.474 5.186 11.128 ms 6.742 26.78

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter SHM(1)

peer jitter SHM(1) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter SHM(1) 0.032 0.093 0.127 0.248 0.511 0.695 7.317 0.384 0.602 0.178 0.279 µs 16.34 459

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -6.445 -6.426 -6.240 -5.715 -5.457 -5.423 -5.418 0.782 1.003 0.249 -5.782 ppm -1.429e+04 3.48e+05
Local Clock Time Offset -13.620 -1.369 -1.056 0.023 1.070 1.351 2.370 2.126 2.720 0.756 0.006 µs -5.937 44.24
Local RMS Frequency Jitter 22.000 40.000 54.000 177.000 378.000 491.000 4,214.000 324.000 451.000 152.799 194.756 10e-12 12.17 248.2
Local RMS Time Jitter 93.000 151.000 177.000 263.000 390.000 470.000 3,273.000 213.000 319.000 104.216 274.496 ns 21.44 364
Server Jitter 104.131.155.175 0.000 0.000 0.381 2.059 11.412 25.432 139.704 11.030 25.432 8.789 4.351 ms 9.684 143.9
Server Jitter 169.229.128.134 0.000 0.198 0.343 2.152 10.559 18.470 136.384 10.217 18.272 7.319 4.103 ms 8.83 131.7
Server Jitter 178.62.68.79 0.000 0.442 0.979 4.683 13.412 20.295 32.437 12.433 19.853 4.499 5.845 ms 2.845 12.26
Server Jitter 192.168.1.10 0.005 0.012 0.022 0.142 8.721 14.394 303.554 8.699 14.382 7.133 2.130 ms 23.37 856.7
Server Jitter 203.123.48.219 0.000 0.290 0.490 2.599 14.857 26.065 147.925 14.367 25.775 7.888 4.972 ms 9.388 164.5
Server Jitter 204.17.205.24 0.128 0.278 0.441 2.296 12.177 19.453 117.371 11.735 19.174 5.988 4.343 ms 7.644 128.5
Server Jitter 216.218.192.202 0.000 0.216 0.367 1.976 9.765 17.864 141.526 9.398 17.648 6.454 3.773 ms 10.24 183.2
Server Jitter 216.218.254.202 0.151 0.220 0.404 2.627 11.727 18.455 76.399 11.323 18.235 5.173 4.367 ms 5.71 72.42
Server Jitter SHM(0) 0.919 3.850 5.199 9.951 20.860 29.324 68.987 15.661 25.474 5.186 11.128 ms 6.742 26.78
Server Jitter SHM(1) 0.032 0.093 0.127 0.248 0.511 0.695 7.317 0.384 0.602 0.178 0.279 µs 16.34 459
Server Offset 104.131.155.175 -0.746 1.334 1.601 2.673 3.585 3.985 15.511 1.984 2.651 0.749 2.643 ms 28.45 210.3
Server Offset 169.229.128.134 0.269 2.048 2.290 2.606 3.022 3.391 4.114 0.733 1.343 0.264 2.619 ms 736.1 6802
Server Offset 178.62.68.79 -14.817 -10.722 -5.211 3.209 12.084 15.449 18.971 17.295 26.170 5.107 3.364 ms -1.183 4.693
Server Offset 192.168.1.10 -92.462 19.049 49.085 86.921 114.383 134.703 205.458 65.298 115.654 21.576 84.883 µs 33.15 122.6
Server Offset 203.123.48.219 -5.815 -2.196 2.691 4.305 25.883 26.519 33.462 23.192 28.716 7.118 6.754 ms 2.073 6.169
Server Offset 204.17.205.24 1.000 1.333 1.557 1.964 2.490 2.941 3.671 0.933 1.609 0.294 1.989 ms 210.1 1332
Server Offset 216.218.192.202 -1.135 2.040 2.213 2.499 2.919 3.220 4.441 0.706 1.179 0.246 2.521 ms 820.3 7850
Server Offset 216.218.254.202 1.916 2.083 2.291 2.591 3.018 3.333 3.603 0.727 1.250 0.228 2.615 ms 1174 1.262e+04
Server Offset SHM(0) -438.810 -389.439 -374.306 -340.773 -294.615 -269.769 -236.037 79.691 119.670 24.098 -338.614 ms -3455 5.266e+04
Server Offset SHM(1) -13.621 -1.370 -1.057 0.024 1.071 1.352 2.371 2.128 2.722 0.757 0.006 µs -5.932 44.11
TDOP 0.580 0.640 0.730 1.070 1.750 2.390 4.750 1.020 1.750 0.361 1.157 19.66 90.16
Temp ZONE0 59.072 60.148 60.148 62.838 66.604 67.142 68.218 6.456 6.994 1.823 63.079 °C
nSats 4.000 6.000 6.000 8.000 10.000 11.000 12.000 4.000 5.000 1.134 8.279 nSat 268.8 1814
Summary as CSV file


Glossary:

frequency offset:
The difference between the ntpd calculated frequency and the local system clock frequency (usually in parts per million, ppm)
jitter, dispersion:
The short term change in a value. NTP measures Local Time Jitter, Refclock Jitter, and Server Jitter in seconds. Local Frequency Jitter is in ppm or ppb.
kurtosis, Kurt:
The kurtosis of a random variable X is the fourth standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of kurtosis. A normal distribution has a kurtosis of three. NIST describes a kurtosis over three as "heavy tailed" and one under three as "light tailed".
ms, millisecond:
One thousandth of a second = 0.001 seconds, 1e-3 seconds
mu, mean:
The arithmetic mean: the sum of all the values divided by the number of values. The formula for mu is: "mu = (∑xi) / N". Where xi denotes the data points and N is the number of data points.
ns, nanosecond:
One billionth of a second, also one thousandth of a microsecond, 0.000000001 seconds and 1e-9 seconds.
percentile:
The value below which a given percentage of values fall.
ppb, parts per billion:
Ratio between two values. These following are all the same: 1 ppb, one in one billion, 1/1,000,000,000, 0.000,000,001, 1e-9 and 0.000,000,1%
ppm, parts per million:
Ratio between two values. These following are all the same: 1 ppm, one in one million, 1/1,000,000, 0.000,001, and 0.000,1%
‰, parts per thousand:
Ratio between two values. These following are all the same: 1 ‰. one in one thousand, 1/1,000, 0.001, and 0.1%
refclock:
Reference clock, a local GPS module or other local source of time.
remote clock:
Any clock reached over the network, LAN or WAN. Also called a peer or server.
time offset:
The difference between the ntpd calculated time and the local system clock's time. Also called phase offset.
σ, sigma:
Sigma denotes the standard deviation (SD) and is centered on the arithmetic mean of the data set. The SD is simply the square root of the variance of the data set. Two sigma is simply twice the standard deviation. Three sigma is three times sigma. Smaller is better.
The formula for sigma is: "σ = √[ ∑(xi-mu)^2 / N ]". Where xi denotes the data points and N is the number of data points.
skewness, Skew:
The skewness of a random variable X is the third standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of skewness. Wikipedia describes it best: "The qualitative interpretation of the skew is complicated and unintuitive."
A normal distribution has a skewness of zero.
upstream clock:
Any server or reference clock used as a source of time.
µs, us, microsecond:
One millionth of a second, also one thousandth of a millisecond, 0.000,001 seconds, and 1e-6 seconds.



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