NTPsec

A-ntpsec-12-hour-stats

Report generated: Sun Aug 18 18:06:43 2019 UTC
Start Time: Sun Aug 18 06:06:41 2019 UTC
End Time: Sun Aug 18 18:06:41 2019 UTC
Report published: Sun Aug 18 11:06:57 2019 PDT
Report Period: 0.5 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 -615.000 -348.000 -215.000 118.000 577.000 745.000 917.000 792.000 1,093.000 237.771 138.549 ns -0.9304 3.525
Local Clock Frequency Offset -673.294 -672.318 -670.288 -594.635 -574.646 -573.578 -573.395 95.642 98.740 30.241 -605.586 ppb -9359 1.982e+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 95.000 108.000 123.000 177.000 243.000 277.000 332.000 120.000 169.000 36.108 179.609 ns 75.15 354.8

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 20.000 27.000 30.000 48.000 145.000 224.000 297.000 115.000 197.000 39.947 63.351 10e-12 4.061 15.34

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 -615.000 -348.000 -215.000 118.000 577.000 745.000 917.000 792.000 1,093.000 237.771 138.549 ns -0.9304 3.525

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 -673.294 -672.318 -670.288 -594.635 -574.646 -573.578 -573.395 95.642 98.740 30.241 -605.586 ppb -9359 1.982e+05
Temp ZONE0 59.072 59.072 59.072 60.148 61.224 61.224 61.224 2.152 2.152 0.483 60.119 °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 7.000 7.000 9.000 12.000 12.000 12.000 5.000 5.000 1.337 9.182 nSat 219.8 1399
TDOP 0.530 0.550 0.610 0.820 1.560 1.790 5.360 0.950 1.240 0.325 0.912 15.7 113.2

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 0.173 0.173 0.535 2.817 3.932 4.192 4.192 3.396 4.020 1.021 2.480 ms 6.744 16.01

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 -4.423 -4.423 -4.138 1.156 8.375 9.276 9.276 12.512 13.699 3.863 1.279 ms -2.035 4.051

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 192.168.1.11

peer offset 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.11 -69.321 -40.472 -29.726 6.258 55.923 98.089 146.606 85.649 138.561 28.101 8.402 µs -1.483 5.883

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 192.168.1.12

peer offset 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.12 -70.167 -36.600 -25.801 12.623 58.998 94.700 130.333 84.799 131.300 26.711 13.769 µs -1.019 4.33

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 0.815 0.913 1.071 1.370 2.585 4.988 5.526 1.514 4.075 0.663 1.621 ms 10.26 48.5

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 1.008 1.083 1.330 1.747 2.203 2.441 2.525 0.873 1.359 0.256 1.750 ms 217.6 1381

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 1.959 2.046 2.235 2.521 2.830 3.214 3.405 0.596 1.168 0.198 2.533 ms 1685 2.036e+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 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 2.046 2.049 2.234 2.511 2.838 3.229 3.363 0.605 1.180 0.194 2.520 ms 1761 2.158e+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) -69.561 -60.210 -57.820 -50.346 -45.421 -44.170 -42.349 12.399 16.040 3.922 -50.956 ms -2782 3.953e+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) -616.000 -349.000 -216.000 119.000 578.000 746.000 918.000 794.000 1,095.000 238.400 138.941 ns -0.936 3.525

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 0.280 1.496 99.408 149.076 149.076 99.128 149.076 28.066 10.533 ms 1.915 10.57

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 0.000 2.490 169.703 170.164 170.164 169.703 170.164 45.590 18.144 ms 0.8711 5.016

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 192.168.1.11

peer jitter 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.11 0.012 0.017 0.031 0.118 8.602 8.716 12.262 8.571 8.699 2.390 1.090 ms 0.7193 4.385

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 192.168.1.12

peer jitter 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.12 0.011 0.015 0.031 0.120 8.696 10.138 14.248 8.665 10.123 2.656 1.245 ms 0.6383 4.117

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 0.115 0.169 0.291 1.229 9.793 205.342 205.763 9.502 205.172 23.202 4.980 ms 5.547 50.26

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 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 0.176 0.202 0.293 1.289 9.778 12.480 12.746 9.485 12.278 2.992 2.381 ms 1.347 4.704

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 0.116 0.118 0.218 0.832 10.414 17.758 19.888 10.196 17.641 4.028 2.566 ms 1.307 5.939

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 0.155 0.195 0.241 1.034 8.830 9.839 20.095 8.589 9.644 2.898 2.063 ms 1.926 10.63

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) 0.105 0.334 0.500 1.252 3.099 5.309 14.641 2.599 4.975 0.956 1.489 ms 4.256 21.92

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) 49.000 68.000 93.000 172.000 327.000 414.000 653.000 234.000 346.000 73.668 186.981 ns 9.407 32.01

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 -673.294 -672.318 -670.288 -594.635 -574.646 -573.578 -573.395 95.642 98.740 30.241 -605.586 ppb -9359 1.982e+05
Local Clock Time Offset -615.000 -348.000 -215.000 118.000 577.000 745.000 917.000 792.000 1,093.000 237.771 138.549 ns -0.9304 3.525
Local RMS Frequency Jitter 20.000 27.000 30.000 48.000 145.000 224.000 297.000 115.000 197.000 39.947 63.351 10e-12 4.061 15.34
Local RMS Time Jitter 95.000 108.000 123.000 177.000 243.000 277.000 332.000 120.000 169.000 36.108 179.609 ns 75.15 354.8
Server Jitter 104.131.155.175 0.000 0.000 0.280 1.496 99.408 149.076 149.076 99.128 149.076 28.066 10.533 ms 1.915 10.57
Server Jitter 178.62.68.79 0.000 0.000 0.000 2.490 169.703 170.164 170.164 169.703 170.164 45.590 18.144 ms 0.8711 5.016
Server Jitter 192.168.1.11 0.012 0.017 0.031 0.118 8.602 8.716 12.262 8.571 8.699 2.390 1.090 ms 0.7193 4.385
Server Jitter 192.168.1.12 0.011 0.015 0.031 0.120 8.696 10.138 14.248 8.665 10.123 2.656 1.245 ms 0.6383 4.117
Server Jitter 203.123.48.219 0.115 0.169 0.291 1.229 9.793 205.342 205.763 9.502 205.172 23.202 4.980 ms 5.547 50.26
Server Jitter 204.17.205.24 0.176 0.202 0.293 1.289 9.778 12.480 12.746 9.485 12.278 2.992 2.381 ms 1.347 4.704
Server Jitter 216.218.254.202 0.116 0.118 0.218 0.832 10.414 17.758 19.888 10.196 17.641 4.028 2.566 ms 1.307 5.939
Server Jitter 66.220.9.122 0.155 0.195 0.241 1.034 8.830 9.839 20.095 8.589 9.644 2.898 2.063 ms 1.926 10.63
Server Jitter SHM(0) 0.105 0.334 0.500 1.252 3.099 5.309 14.641 2.599 4.975 0.956 1.489 ms 4.256 21.92
Server Jitter SHM(1) 49.000 68.000 93.000 172.000 327.000 414.000 653.000 234.000 346.000 73.668 186.981 ns 9.407 32.01
Server Offset 104.131.155.175 0.173 0.173 0.535 2.817 3.932 4.192 4.192 3.396 4.020 1.021 2.480 ms 6.744 16.01
Server Offset 178.62.68.79 -4.423 -4.423 -4.138 1.156 8.375 9.276 9.276 12.512 13.699 3.863 1.279 ms -2.035 4.051
Server Offset 192.168.1.11 -69.321 -40.472 -29.726 6.258 55.923 98.089 146.606 85.649 138.561 28.101 8.402 µs -1.483 5.883
Server Offset 192.168.1.12 -70.167 -36.600 -25.801 12.623 58.998 94.700 130.333 84.799 131.300 26.711 13.769 µs -1.019 4.33
Server Offset 203.123.48.219 0.815 0.913 1.071 1.370 2.585 4.988 5.526 1.514 4.075 0.663 1.621 ms 10.26 48.5
Server Offset 204.17.205.24 1.008 1.083 1.330 1.747 2.203 2.441 2.525 0.873 1.359 0.256 1.750 ms 217.6 1381
Server Offset 216.218.254.202 1.959 2.046 2.235 2.521 2.830 3.214 3.405 0.596 1.168 0.198 2.533 ms 1685 2.036e+04
Server Offset 66.220.9.122 2.046 2.049 2.234 2.511 2.838 3.229 3.363 0.605 1.180 0.194 2.520 ms 1761 2.158e+04
Server Offset SHM(0) -69.561 -60.210 -57.820 -50.346 -45.421 -44.170 -42.349 12.399 16.040 3.922 -50.956 ms -2782 3.953e+04
Server Offset SHM(1) -616.000 -349.000 -216.000 119.000 578.000 746.000 918.000 794.000 1,095.000 238.400 138.941 ns -0.936 3.525
TDOP 0.530 0.550 0.610 0.820 1.560 1.790 5.360 0.950 1.240 0.325 0.912 15.7 113.2
Temp ZONE0 59.072 59.072 59.072 60.148 61.224 61.224 61.224 2.152 2.152 0.483 60.119 °C
nSats 5.000 7.000 7.000 9.000 12.000 12.000 12.000 5.000 5.000 1.337 9.182 nSat 219.8 1399
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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