NTPsec

b-ntpsec-72-hour-stats

Report generated: Thu Apr 2 03:03:02 2020 UTC
Start Time: Mon Mar 30 03:02:57 2020 UTC
End Time: Thu Apr 2 03:02:57 2020 UTC
Report published: Wed Apr 01 20:03:19 2020 PDT
Report Period: 3.0 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 -6.907 -0.965 -0.705 -0.020 0.758 1.002 4.687 1.463 1.967 0.479 -0.000 µs -4.614 21.96
Local Clock Frequency Offset -5.828 -5.826 -5.807 -5.695 -5.566 -5.546 -5.543 0.241 0.280 0.072 -5.684 ppm -5.07e+05 4.044e+07

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 125.000 162.000 193.000 294.000 450.000 593.000 3,352.000 257.000 431.000 137.531 311.322 ns 14.92 197.5

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 0.031 0.040 0.048 0.099 0.188 0.699 16.079 0.140 0.659 0.427 0.135 ppb 19.04 531.3

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 -6.907 -0.965 -0.705 -0.020 0.758 1.002 4.687 1.463 1.967 0.479 -0.000 µs -4.614 21.96

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 -5.828 -5.826 -5.807 -5.695 -5.566 -5.546 -5.543 0.241 0.280 0.072 -5.684 ppm -5.07e+05 4.044e+07
Temp ZONE0 60.148 60.148 60.686 62.300 63.376 63.376 63.914 2.690 3.228 0.722 62.056 °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 5.000 6.000 7.000 9.000 11.000 11.000 12.000 4.000 5.000 1.206 8.794 nSat 268 1807
TDOP 0.520 0.600 0.630 0.940 1.600 1.820 4.540 0.970 1.220 0.314 0.992 19 88.66

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. TDOP ranges from 1 to greater than 20. 1 denotes the highest possible confidence level. 2 to 5 is good. Greater than 20 means there will be significant inaccuracy and error.



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 0.688 1.389 1.932 2.887 4.730 5.942 6.906 2.798 4.553 0.910 3.063 ms 21.3 78.36

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 -1.961 1.766 1.954 2.285 2.811 3.213 5.158 0.857 1.448 0.341 2.320 ms 211.8 1368

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 -7.554 -6.502 -1.519 3.802 10.279 14.277 17.314 11.798 20.780 3.638 3.965 ms 0.5526 4.962

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 -35.966 26.325 51.134 89.542 131.378 148.884 222.508 80.244 122.559 25.011 89.569 µs 24.98 89.35

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 -1.215 -0.027 0.266 0.889 3.332 3.856 5.441 3.066 3.882 1.188 1.537 ms 1.377 2.84

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 -0.451 1.288 1.619 2.018 2.827 7.119 9.639 1.208 5.832 0.803 2.158 ms 15.11 99.24

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 0.714 2.064 2.254 2.565 3.137 3.519 9.088 0.883 1.455 0.390 2.620 ms 211 1518

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 0.287 2.178 2.327 2.647 3.175 3.963 5.117 0.847 1.785 0.351 2.681 ms 313.4 2259

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 76.14.161.109

peer offset 76.14.161.109 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 76.14.161.109 -13.210 -10.684 -7.853 -0.926 1.431 3.445 4.914 9.285 14.129 2.686 -1.633 ms -10.43 37.05

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) -430.207 -396.169 -385.797 -351.097 -308.511 -286.120 -248.082 77.287 110.049 23.621 -349.893 ms -4001 6.4e+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) -6.908 -0.967 -0.706 -0.020 0.761 1.013 5.207 1.467 1.980 0.486 0.001 µs -4.339 22.33

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 0.226 0.409 1.918 10.034 16.372 239.997 9.625 16.146 14.050 4.192 ms 12.73 208.6

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 0.225 0.413 2.084 9.851 14.850 83.913 9.438 14.625 5.015 3.502 ms 8.801 138.7

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 0.000 0.414 3.432 11.672 26.622 38.495 11.259 26.622 4.773 4.912 ms 2.716 15.96

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 0.000 0.012 0.021 0.119 8.658 9.781 14.071 8.637 9.769 2.749 1.355 ms 0.5298 3.658

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 0.295 0.446 2.235 10.153 19.698 246.463 9.708 19.404 12.556 4.396 ms 15.3 294.3

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 0.000 0.227 0.367 1.897 10.179 16.853 167.723 9.812 16.626 12.173 4.220 ms 9.38 123.2

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 216.218.192.202

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 0.182 0.335 1.842 10.110 21.564 254.179 9.776 21.382 14.999 4.296 ms 10.88 170.9

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 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 0.000 0.000 0.394 2.003 9.620 19.871 24.941 9.226 19.871 3.719 3.413 ms 2.322 11.41

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 76.14.161.109

peer jitter 76.14.161.109 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 76.14.161.109 0.000 0.939 1.797 11.688 40.705 67.710 125.238 38.908 66.771 15.047 15.986 ms 2.675 14.31

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) 0.000 4.220 5.682 10.847 21.943 29.486 56.573 16.261 25.267 5.237 11.973 ms 7.429 26.56

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) 0.000 0.103 0.139 0.266 0.532 0.744 7.927 0.393 0.641 0.206 0.300 µs 13.18 282.6

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 -5.828 -5.826 -5.807 -5.695 -5.566 -5.546 -5.543 0.241 0.280 0.072 -5.684 ppm -5.07e+05 4.044e+07
Local Clock Time Offset -6.907 -0.965 -0.705 -0.020 0.758 1.002 4.687 1.463 1.967 0.479 -0.000 µs -4.614 21.96
Local RMS Frequency Jitter 0.031 0.040 0.048 0.099 0.188 0.699 16.079 0.140 0.659 0.427 0.135 ppb 19.04 531.3
Local RMS Time Jitter 125.000 162.000 193.000 294.000 450.000 593.000 3,352.000 257.000 431.000 137.531 311.322 ns 14.92 197.5
Server Jitter 104.131.155.175 0.000 0.226 0.409 1.918 10.034 16.372 239.997 9.625 16.146 14.050 4.192 ms 12.73 208.6
Server Jitter 169.229.128.134 0.000 0.225 0.413 2.084 9.851 14.850 83.913 9.438 14.625 5.015 3.502 ms 8.801 138.7
Server Jitter 178.62.68.79 0.000 0.000 0.414 3.432 11.672 26.622 38.495 11.259 26.622 4.773 4.912 ms 2.716 15.96
Server Jitter 192.168.1.10 0.000 0.012 0.021 0.119 8.658 9.781 14.071 8.637 9.769 2.749 1.355 ms 0.5298 3.658
Server Jitter 203.123.48.219 0.000 0.295 0.446 2.235 10.153 19.698 246.463 9.708 19.404 12.556 4.396 ms 15.3 294.3
Server Jitter 204.17.205.24 0.000 0.227 0.367 1.897 10.179 16.853 167.723 9.812 16.626 12.173 4.220 ms 9.38 123.2
Server Jitter 216.218.192.202 0.000 0.182 0.335 1.842 10.110 21.564 254.179 9.776 21.382 14.999 4.296 ms 10.88 170.9
Server Jitter 216.218.254.202 0.000 0.000 0.394 2.003 9.620 19.871 24.941 9.226 19.871 3.719 3.413 ms 2.322 11.41
Server Jitter 76.14.161.109 0.000 0.939 1.797 11.688 40.705 67.710 125.238 38.908 66.771 15.047 15.986 ms 2.675 14.31
Server Jitter SHM(0) 0.000 4.220 5.682 10.847 21.943 29.486 56.573 16.261 25.267 5.237 11.973 ms 7.429 26.56
Server Jitter SHM(1) 0.000 0.103 0.139 0.266 0.532 0.744 7.927 0.393 0.641 0.206 0.300 µs 13.18 282.6
Server Offset 104.131.155.175 0.688 1.389 1.932 2.887 4.730 5.942 6.906 2.798 4.553 0.910 3.063 ms 21.3 78.36
Server Offset 169.229.128.134 -1.961 1.766 1.954 2.285 2.811 3.213 5.158 0.857 1.448 0.341 2.320 ms 211.8 1368
Server Offset 178.62.68.79 -7.554 -6.502 -1.519 3.802 10.279 14.277 17.314 11.798 20.780 3.638 3.965 ms 0.5526 4.962
Server Offset 192.168.1.10 -35.966 26.325 51.134 89.542 131.378 148.884 222.508 80.244 122.559 25.011 89.569 µs 24.98 89.35
Server Offset 203.123.48.219 -1.215 -0.027 0.266 0.889 3.332 3.856 5.441 3.066 3.882 1.188 1.537 ms 1.377 2.84
Server Offset 204.17.205.24 -0.451 1.288 1.619 2.018 2.827 7.119 9.639 1.208 5.832 0.803 2.158 ms 15.11 99.24
Server Offset 216.218.192.202 0.714 2.064 2.254 2.565 3.137 3.519 9.088 0.883 1.455 0.390 2.620 ms 211 1518
Server Offset 216.218.254.202 0.287 2.178 2.327 2.647 3.175 3.963 5.117 0.847 1.785 0.351 2.681 ms 313.4 2259
Server Offset 76.14.161.109 -13.210 -10.684 -7.853 -0.926 1.431 3.445 4.914 9.285 14.129 2.686 -1.633 ms -10.43 37.05
Server Offset SHM(0) -430.207 -396.169 -385.797 -351.097 -308.511 -286.120 -248.082 77.287 110.049 23.621 -349.893 ms -4001 6.4e+04
Server Offset SHM(1) -6.908 -0.967 -0.706 -0.020 0.761 1.013 5.207 1.467 1.980 0.486 0.001 µs -4.339 22.33
TDOP 0.520 0.600 0.630 0.940 1.600 1.820 4.540 0.970 1.220 0.314 0.992 19 88.66
Temp ZONE0 60.148 60.148 60.686 62.300 63.376 63.376 63.914 2.690 3.228 0.722 62.056 °C
nSats 5.000 6.000 7.000 9.000 11.000 11.000 12.000 4.000 5.000 1.206 8.794 nSat 268 1807
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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