NTPsec

C-ntpsec-6-hour-stats

Report generated: Thu Apr 2 03:01:45 2020 UTC
Start Time: Wed Apr 1 21:01:44 2020 UTC
End Time: Thu Apr 2 03:01:44 2020 UTC
Report published: Wed Apr 01 20:01:49 2020 PDT
Report Period: 0.2 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 -727.000 -556.000 -409.000 -91.000 286.000 513.000 627.000 695.000 1,069.000 214.928 -80.513 ns -6.431 16.51
Local Clock Frequency Offset -5.553 -5.553 -5.552 -5.542 -5.526 -5.525 -5.525 0.027 0.028 0.0088 -5.541 ppm -2.543e+08 1.611e+11

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 81.000 93.000 109.000 164.000 240.000 270.000 305.000 131.000 177.000 38.658 167.418 ns 47.45 199.5

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 22.000 25.000 32.000 52.000 81.000 108.000 121.000 49.000 83.000 16.082 54.321 10e-12 21.46 78.77

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 -727.000 -556.000 -409.000 -91.000 286.000 513.000 627.000 695.000 1,069.000 214.928 -80.513 ns -6.431 16.51

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 -5.553 -5.553 -5.552 -5.542 -5.526 -5.525 -5.525 0.027 0.028 0.0088 -5.541 ppm -2.543e+08 1.611e+11
Temp ZONE0 64.990 64.990 65.528 65.528 66.604 66.604 66.604 1.076 1.614 0.418 65.862 °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 7.000 9.000 11.000 11.000 11.000 4.000 4.000 0.984 8.844 nSat 534.7 4473
TDOP 0.600 0.620 0.640 0.930 1.620 1.690 1.750 0.980 1.070 0.269 0.955 25.46 96.91

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 1.547 1.547 1.908 2.618 3.413 3.674 3.674 1.505 2.127 0.475 2.616 ms 105.2 539.5

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 162.159.200.1

peer offset 162.159.200.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 162.159.200.1 0.686 0.686 0.743 1.232 1.695 2.185 2.185 0.952 1.499 0.276 1.253 ms 55.6 243.3

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 164.67.62.194

peer offset 164.67.62.194 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 164.67.62.194 2.332 2.332 2.477 2.743 3.176 3.450 3.450 0.699 1.119 0.224 2.775 ms 1506 1.753e+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 173.11.101.155

peer offset 173.11.101.155 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 173.11.101.155 -2.078 -2.078 -0.844 0.217 0.964 1.361 1.361 1.808 3.439 0.572 0.080 ms -4.291 13.89

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 -1.439 -1.439 -1.439 8.427 10.716 10.716 10.716 12.154 12.154 3.073 7.091 ms 4.995 11.06

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 -44.946 -32.285 -8.937 57.118 125.598 146.816 220.562 134.535 179.101 40.348 57.654 µs 1.567 4.816

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 -2.000 -2.000 -1.746 -0.673 -0.009 0.240 0.240 1.738 2.240 0.527 -0.786 ms -23.45 83.62

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 1.044 1.044 1.621 2.015 2.636 2.738 2.738 1.015 1.694 0.325 2.051 ms 166.4 972.5

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 47.51.249.154

peer offset 47.51.249.154 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 47.51.249.154 1.620 1.620 2.157 3.475 4.246 4.450 4.450 2.089 2.829 0.621 3.382 ms 100.9 502.7

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) -61.465 -59.246 -58.371 -52.434 -45.640 -44.801 -43.806 12.731 14.445 4.071 -52.067 ms -2664 3.73e+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) -728.000 -557.000 -410.000 -92.000 287.000 514.000 628.000 697.000 1,071.000 215.637 -80.817 ns -6.431 16.49

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 0.493 0.493 0.595 2.339 10.539 13.433 13.433 9.945 12.940 3.200 3.386 ms 1.791 5.014

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 162.159.200.1

peer jitter 162.159.200.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 162.159.200.1 0.469 0.469 0.850 2.020 8.141 10.021 10.021 7.291 9.552 2.016 2.732 ms 3.186 10.98

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 164.67.62.194

peer jitter 164.67.62.194 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 164.67.62.194 0.354 0.354 0.635 2.397 10.247 10.840 10.840 9.611 10.486 3.026 3.929 ms 1.916 4.358

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 173.11.101.155

peer jitter 173.11.101.155 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 173.11.101.155 0.707 0.707 0.999 2.389 11.407 14.693 14.693 10.408 13.987 3.511 4.235 ms 2.121 5.932

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 0.746 0.746 0.746 6.998 9.732 9.732 9.732 8.986 8.986 2.879 6.685 ms 5.53 11.94

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 0.008 0.041 0.059 0.149 8.121 9.283 12.289 8.063 9.242 2.215 0.932 ms 1.188 6.861

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 0.318 0.318 0.627 2.873 10.511 13.902 13.902 9.884 13.584 3.434 4.163 ms 1.79 4.479

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 0.888 0.888 1.116 2.663 11.033 12.724 12.724 9.917 11.836 2.733 3.542 ms 2.808 8.553

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 47.51.249.154

peer jitter 47.51.249.154 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 47.51.249.154 1.027 1.027 1.758 2.973 9.889 24.810 24.810 8.131 23.783 3.361 4.147 ms 4.297 24.23

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) 0.132 0.296 0.479 1.962 6.667 7.539 8.302 6.188 7.243 2.053 2.695 ms 1.767 4.022

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) 29.000 66.000 89.000 193.000 414.000 541.000 745.000 325.000 475.000 102.718 213.780 ns 5.744 18.72

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 -5.553 -5.553 -5.552 -5.542 -5.526 -5.525 -5.525 0.027 0.028 0.0088 -5.541 ppm -2.543e+08 1.611e+11
Local Clock Time Offset -727.000 -556.000 -409.000 -91.000 286.000 513.000 627.000 695.000 1,069.000 214.928 -80.513 ns -6.431 16.51
Local RMS Frequency Jitter 22.000 25.000 32.000 52.000 81.000 108.000 121.000 49.000 83.000 16.082 54.321 10e-12 21.46 78.77
Local RMS Time Jitter 81.000 93.000 109.000 164.000 240.000 270.000 305.000 131.000 177.000 38.658 167.418 ns 47.45 199.5
Server Jitter 104.131.155.175 0.493 0.493 0.595 2.339 10.539 13.433 13.433 9.945 12.940 3.200 3.386 ms 1.791 5.014
Server Jitter 162.159.200.1 0.469 0.469 0.850 2.020 8.141 10.021 10.021 7.291 9.552 2.016 2.732 ms 3.186 10.98
Server Jitter 164.67.62.194 0.354 0.354 0.635 2.397 10.247 10.840 10.840 9.611 10.486 3.026 3.929 ms 1.916 4.358
Server Jitter 173.11.101.155 0.707 0.707 0.999 2.389 11.407 14.693 14.693 10.408 13.987 3.511 4.235 ms 2.121 5.932
Server Jitter 178.62.68.79 0.746 0.746 0.746 6.998 9.732 9.732 9.732 8.986 8.986 2.879 6.685 ms 5.53 11.94
Server Jitter 192.168.1.10 0.008 0.041 0.059 0.149 8.121 9.283 12.289 8.063 9.242 2.215 0.932 ms 1.188 6.861
Server Jitter 203.123.48.219 0.318 0.318 0.627 2.873 10.511 13.902 13.902 9.884 13.584 3.434 4.163 ms 1.79 4.479
Server Jitter 204.17.205.24 0.888 0.888 1.116 2.663 11.033 12.724 12.724 9.917 11.836 2.733 3.542 ms 2.808 8.553
Server Jitter 47.51.249.154 1.027 1.027 1.758 2.973 9.889 24.810 24.810 8.131 23.783 3.361 4.147 ms 4.297 24.23
Server Jitter SHM(0) 0.132 0.296 0.479 1.962 6.667 7.539 8.302 6.188 7.243 2.053 2.695 ms 1.767 4.022
Server Jitter SHM(1) 29.000 66.000 89.000 193.000 414.000 541.000 745.000 325.000 475.000 102.718 213.780 ns 5.744 18.72
Server Offset 104.131.155.175 1.547 1.547 1.908 2.618 3.413 3.674 3.674 1.505 2.127 0.475 2.616 ms 105.2 539.5
Server Offset 162.159.200.1 0.686 0.686 0.743 1.232 1.695 2.185 2.185 0.952 1.499 0.276 1.253 ms 55.6 243.3
Server Offset 164.67.62.194 2.332 2.332 2.477 2.743 3.176 3.450 3.450 0.699 1.119 0.224 2.775 ms 1506 1.753e+04
Server Offset 173.11.101.155 -2.078 -2.078 -0.844 0.217 0.964 1.361 1.361 1.808 3.439 0.572 0.080 ms -4.291 13.89
Server Offset 178.62.68.79 -1.439 -1.439 -1.439 8.427 10.716 10.716 10.716 12.154 12.154 3.073 7.091 ms 4.995 11.06
Server Offset 192.168.1.10 -44.946 -32.285 -8.937 57.118 125.598 146.816 220.562 134.535 179.101 40.348 57.654 µs 1.567 4.816
Server Offset 203.123.48.219 -2.000 -2.000 -1.746 -0.673 -0.009 0.240 0.240 1.738 2.240 0.527 -0.786 ms -23.45 83.62
Server Offset 204.17.205.24 1.044 1.044 1.621 2.015 2.636 2.738 2.738 1.015 1.694 0.325 2.051 ms 166.4 972.5
Server Offset 47.51.249.154 1.620 1.620 2.157 3.475 4.246 4.450 4.450 2.089 2.829 0.621 3.382 ms 100.9 502.7
Server Offset SHM(0) -61.465 -59.246 -58.371 -52.434 -45.640 -44.801 -43.806 12.731 14.445 4.071 -52.067 ms -2664 3.73e+04
Server Offset SHM(1) -728.000 -557.000 -410.000 -92.000 287.000 514.000 628.000 697.000 1,071.000 215.637 -80.817 ns -6.431 16.49
TDOP 0.600 0.620 0.640 0.930 1.620 1.690 1.750 0.980 1.070 0.269 0.955 25.46 96.91
Temp ZONE0 64.990 64.990 65.528 65.528 66.604 66.604 66.604 1.076 1.614 0.418 65.862 °C
nSats 7.000 7.000 7.000 9.000 11.000 11.000 11.000 4.000 4.000 0.984 8.844 nSat 534.7 4473
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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