NTPsec

B-ntpsec-3-hour-stats

Report generated: Wed Oct 23 21:04:15 2019 UTC
Start Time: Wed Oct 23 18:04:12 2019 UTC
End Time: Wed Oct 23 21:04:12 2019 UTC
Report published: Wed Oct 23 14:04:33 2019 PDT
Report Period: 0.1 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 -614.000 -535.000 -379.000 -37.000 296.000 400.000 530.000 675.000 935.000 205.355 -40.634 ns -5.356 13.6
Local Clock Frequency Offset -5.701 -5.701 -5.700 -5.697 -5.695 -5.694 -5.694 0.0049 0.0062 0.0016 -5.697 ppm -4.597e+10 1.647e+14

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 101.000 142.000 168.000 252.000 357.000 428.000 449.000 189.000 286.000 58.275 254.687 ns 48.9 207.4

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 28.000 31.000 36.000 50.000 68.000 80.000 88.000 32.000 49.000 10.083 51.055 10e-12 79.81 383.7

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 -614.000 -535.000 -379.000 -37.000 296.000 400.000 530.000 675.000 935.000 205.355 -40.634 ns -5.356 13.6

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 -5.701 -5.701 -5.700 -5.697 -5.695 -5.694 -5.694 0.0049 0.0062 0.0016 -5.697 ppm -4.597e+10 1.647e+14
Temp ZONE0 59.072 59.072 59.072 60.148 60.148 60.148 60.148 1.076 1.076 0.403 59.787 °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 7.000 7.000 8.000 10.000 11.000 11.000 11.000 3.000 4.000 1.085 9.371 nSat 468.1 3746
TDOP 0.590 0.590 0.600 0.810 1.480 2.070 2.070 0.880 1.480 0.346 0.939 11.26 37.12

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 2.311 2.311 2.311 2.928 3.664 3.664 3.664 1.354 1.354 0.450 3.007 ms 200.9 1240

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 1.697 1.697 1.792 2.279 2.851 3.174 3.174 1.060 1.478 0.325 2.306 ms 245.5 1619

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 1.778 1.778 1.778 6.501 8.894 8.894 8.894 7.116 7.116 2.337 5.754 ms 7.327 18.16

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 -60.195 -29.926 47.187 145.623 231.516 379.026 391.632 184.329 408.952 63.963 144.538 µs 6.425 21.33

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 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 2.367 2.367 2.605 3.580 4.064 4.350 4.350 1.459 1.983 0.468 3.453 ms 278.7 1895

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 0.800 0.800 1.052 1.901 2.706 2.785 2.785 1.654 1.985 0.444 1.932 ms 47.24 191.4

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 66.220.9.122

peer offset 66.220.9.122 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 66.220.9.122 1.878 1.878 2.121 2.820 3.352 3.427 3.427 1.231 1.549 0.363 2.741 ms 300.9 2098

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 -2.922 -2.922 -1.845 -0.453 0.733 2.082 2.082 2.577 5.004 0.895 -0.401 ms -7.436 21.47

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) -458.324 -432.246 -394.460 -365.065 -324.020 -312.435 -290.206 70.440 119.811 22.892 -363.043 ms -4842 8.25e+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) -615.000 -536.000 -380.000 -38.000 297.000 401.000 531.000 677.000 937.000 206.095 -40.769 ns -5.353 13.58

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 0.000 1.230 5.620 5.620 5.620 5.620 5.620 2.305 2.626 ms 0.7303 1.556

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 0.382 0.382 0.513 1.526 75.558 106.521 106.521 75.045 106.139 21.649 7.786 ms 1.599 8.966

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 1.898 1.898 1.898 3.983 5.983 5.983 5.983 4.085 4.085 1.445 3.574 ms 7.91 21.16

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 0.079 0.110 0.191 0.711 75.754 77.350 77.351 75.563 77.240 26.549 11.956 ms 0.1511 2.473

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 0.665 0.665 0.763 2.432 76.189 76.280 76.280 75.426 75.615 27.404 14.527 ms 0.2712 2.212

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 0.799 0.799 1.209 3.386 10.949 75.798 75.798 9.740 74.999 12.221 5.571 ms 3.62 21.24

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 66.220.9.122

peer jitter 66.220.9.122 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 66.220.9.122 0.322 0.322 0.526 2.909 19.677 75.217 75.217 19.150 74.895 11.964 5.729 ms 3.378 20.39

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 1.581 1.581 2.217 17.811 75.985 106.006 106.006 73.768 104.425 27.056 27.975 ms 1.454 3.808

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) 1.866 4.471 6.050 11.581 22.567 29.920 48.956 16.516 25.449 5.406 12.672 ms 7.927 28.84

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) 81.000 92.000 120.000 222.000 431.000 530.000 678.000 311.000 438.000 93.902 240.036 ns 9.612 32.45

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 -5.701 -5.701 -5.700 -5.697 -5.695 -5.694 -5.694 0.0049 0.0062 0.0016 -5.697 ppm -4.597e+10 1.647e+14
Local Clock Time Offset -614.000 -535.000 -379.000 -37.000 296.000 400.000 530.000 675.000 935.000 205.355 -40.634 ns -5.356 13.6
Local RMS Frequency Jitter 28.000 31.000 36.000 50.000 68.000 80.000 88.000 32.000 49.000 10.083 51.055 10e-12 79.81 383.7
Local RMS Time Jitter 101.000 142.000 168.000 252.000 357.000 428.000 449.000 189.000 286.000 58.275 254.687 ns 48.9 207.4
Server Jitter 104.131.155.175 0.000 0.000 0.000 1.230 5.620 5.620 5.620 5.620 5.620 2.305 2.626 ms 0.7303 1.556
Server Jitter 169.229.128.134 0.382 0.382 0.513 1.526 75.558 106.521 106.521 75.045 106.139 21.649 7.786 ms 1.599 8.966
Server Jitter 178.62.68.79 1.898 1.898 1.898 3.983 5.983 5.983 5.983 4.085 4.085 1.445 3.574 ms 7.91 21.16
Server Jitter 192.168.1.10 0.079 0.110 0.191 0.711 75.754 77.350 77.351 75.563 77.240 26.549 11.956 ms 0.1511 2.473
Server Jitter 203.123.48.219 0.665 0.665 0.763 2.432 76.189 76.280 76.280 75.426 75.615 27.404 14.527 ms 0.2712 2.212
Server Jitter 204.17.205.24 0.799 0.799 1.209 3.386 10.949 75.798 75.798 9.740 74.999 12.221 5.571 ms 3.62 21.24
Server Jitter 66.220.9.122 0.322 0.322 0.526 2.909 19.677 75.217 75.217 19.150 74.895 11.964 5.729 ms 3.378 20.39
Server Jitter 76.14.161.109 1.581 1.581 2.217 17.811 75.985 106.006 106.006 73.768 104.425 27.056 27.975 ms 1.454 3.808
Server Jitter SHM(0) 1.866 4.471 6.050 11.581 22.567 29.920 48.956 16.516 25.449 5.406 12.672 ms 7.927 28.84
Server Jitter SHM(1) 81.000 92.000 120.000 222.000 431.000 530.000 678.000 311.000 438.000 93.902 240.036 ns 9.612 32.45
Server Offset 104.131.155.175 2.311 2.311 2.311 2.928 3.664 3.664 3.664 1.354 1.354 0.450 3.007 ms 200.9 1240
Server Offset 169.229.128.134 1.697 1.697 1.792 2.279 2.851 3.174 3.174 1.060 1.478 0.325 2.306 ms 245.5 1619
Server Offset 178.62.68.79 1.778 1.778 1.778 6.501 8.894 8.894 8.894 7.116 7.116 2.337 5.754 ms 7.327 18.16
Server Offset 192.168.1.10 -60.195 -29.926 47.187 145.623 231.516 379.026 391.632 184.329 408.952 63.963 144.538 µs 6.425 21.33
Server Offset 203.123.48.219 2.367 2.367 2.605 3.580 4.064 4.350 4.350 1.459 1.983 0.468 3.453 ms 278.7 1895
Server Offset 204.17.205.24 0.800 0.800 1.052 1.901 2.706 2.785 2.785 1.654 1.985 0.444 1.932 ms 47.24 191.4
Server Offset 66.220.9.122 1.878 1.878 2.121 2.820 3.352 3.427 3.427 1.231 1.549 0.363 2.741 ms 300.9 2098
Server Offset 76.14.161.109 -2.922 -2.922 -1.845 -0.453 0.733 2.082 2.082 2.577 5.004 0.895 -0.401 ms -7.436 21.47
Server Offset SHM(0) -458.324 -432.246 -394.460 -365.065 -324.020 -312.435 -290.206 70.440 119.811 22.892 -363.043 ms -4842 8.25e+04
Server Offset SHM(1) -615.000 -536.000 -380.000 -38.000 297.000 401.000 531.000 677.000 937.000 206.095 -40.769 ns -5.353 13.58
TDOP 0.590 0.590 0.600 0.810 1.480 2.070 2.070 0.880 1.480 0.346 0.939 11.26 37.12
Temp ZONE0 59.072 59.072 59.072 60.148 60.148 60.148 60.148 1.076 1.076 0.403 59.787 °C
nSats 7.000 7.000 8.000 10.000 11.000 11.000 11.000 3.000 4.000 1.085 9.371 nSat 468.1 3746
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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