NTPsec

A-ntpsec-3-hour-stats

Report generated: Tue May 20 07:04:30 2025 UTC
Start Time: Tue May 20 04:04:30 2025 UTC
End Time: Tue May 20 07:04:30 2025 UTC
Report published: Tue May 20 12:04:46 AM 2025 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 -2.726 -1.759 -1.289 -0.017 0.867 1.274 2.764 2.156 3.033 0.649 -0.071 µs -5.099 14.28
Local Clock Frequency Offset -87.875 -87.097 -85.815 -61.584 -39.917 -38.971 -37.796 45.898 48.126 16.496 -61.239 ppb -118.9 629.3

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 0.418 0.480 0.551 0.800 1.151 1.340 1.723 0.600 0.860 0.186 0.824 µs 51.4 222.2

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 171.000 190.000 219.000 298.000 446.000 557.000 663.000 227.000 367.000 72.411 311.874 10e-12 47.23 205.5

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 -2.726 -1.759 -1.289 -0.017 0.867 1.274 2.764 2.156 3.033 0.649 -0.071 µs -5.099 14.28

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 -87.875 -87.097 -85.815 -61.584 -39.917 -38.971 -37.796 45.898 48.126 16.496 -61.239 ppb -118.9 629.3
Temp ZONE0 48.850 48.850 49.388 49.388 49.926 50.464 50.464 0.538 1.614 0.270 49.479 °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 8.000 8.000 9.000 10.000 11.000 11.000 2.000 3.000 0.700 9.274 nSat 1878 2.347e+04
TDOP 0.630 0.630 0.690 0.890 1.180 1.280 1.590 0.490 0.650 0.167 0.877 91.02 457.9

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

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

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



Server Offsets

peer offsets plot

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

Clock Offset is field 5 in the peerstats log file.



Server Offset 15.204.249.252

peer offset 15.204.249.252 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 15.204.249.252 4.068 4.068 4.088 5.328 6.937 7.838 7.838 2.849 3.771 1.030 5.573 ms 99.13 499.7

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 162.159.200.123

peer offset 162.159.200.123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 162.159.200.123 0.337 0.337 0.371 1.494 3.124 3.457 3.457 2.753 3.120 0.691 1.466 ms 5.953 19.05

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 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 1.230 1.230 1.501 2.377 2.834 2.901 2.901 1.333 1.672 0.365 2.345 ms 175.1 1026

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 -3.769 -3.769 -3.444 -1.859 1.447 1.804 1.804 4.891 5.574 1.430 -1.581 ms -14.98 43.27

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 192.12.19.20

peer offset 192.12.19.20 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.12.19.20 1.710 1.710 1.759 2.507 3.464 4.081 4.081 1.705 2.371 0.483 2.520 ms 88.57 444.8

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 50.116.42.84

peer offset 50.116.42.84 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 50.116.42.84 0.785 0.785 0.922 2.285 3.996 4.228 4.228 3.074 3.442 0.875 2.520 ms 12.47 37.17

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 52.10.183.132

peer offset 52.10.183.132 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 52.10.183.132 2.595 2.595 3.208 4.113 6.399 6.411 6.411 3.192 3.816 0.838 4.278 ms 82.37 403.8

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 64.142.122.36

peer offset 64.142.122.36 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 64.142.122.36 1.205 1.205 1.361 2.149 3.985 4.311 4.311 2.624 3.106 0.559 2.201 ms 36.26 160.4

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 1.674 1.674 1.877 2.354 3.049 3.227 3.227 1.172 1.553 0.359 2.363 ms 190.8 1169

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) -98.594 -98.201 -97.684 -96.545 -95.170 -94.711 -93.998 2.514 3.490 0.801 -96.486 ms -1.793e+06 2.179e+08

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) -2.727 -1.760 -1.290 -0.018 0.868 1.275 2.765 2.158 3.035 0.650 -0.071 µs -5.097 14.27

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 15.204.249.252

peer jitter 15.204.249.252 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 15.204.249.252 0.965 0.965 1.042 2.420 7.663 13.283 13.283 6.620 12.318 2.560 3.456 ms 3.11 11.24

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 162.159.200.123

peer jitter 162.159.200.123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 162.159.200.123 0.904 0.904 0.934 3.226 17.202 17.614 17.614 16.268 16.709 4.789 4.974 ms 1.638 4.559

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 0.752 0.752 1.134 2.475 38.029 38.391 38.391 36.895 37.639 10.128 5.981 ms 1.482 5.469

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 1.148 1.148 1.186 3.370 9.876 10.305 10.305 8.690 9.157 2.494 4.319 ms 3.473 8.923

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 192.12.19.20

peer jitter 192.12.19.20 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.12.19.20 1.433 1.433 1.477 3.356 23.458 44.798 44.798 21.981 43.365 8.712 6.144 ms 2.354 10.18

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 50.116.42.84

peer jitter 50.116.42.84 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 50.116.42.84 1.340 1.340 1.350 4.306 15.492 19.126 19.126 14.143 17.786 5.271 7.087 ms 1.702 3.527

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 52.10.183.132

peer jitter 52.10.183.132 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 52.10.183.132 0.879 0.879 0.911 2.732 17.601 17.693 17.693 16.690 16.814 4.897 4.688 ms 1.566 4.282

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 64.142.122.36

peer jitter 64.142.122.36 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 64.142.122.36 1.013 1.013 1.085 2.331 15.782 16.320 16.320 14.697 15.308 4.759 4.692 ms 1.287 3.028

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 0.690 0.690 0.796 2.700 13.825 14.011 14.011 13.029 13.321 4.403 4.353 ms 1.201 2.783

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) 0.072 0.091 0.120 0.306 0.970 1.303 1.763 0.851 1.212 0.274 0.399 ms 2.913 9.137

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) 0.183 0.320 0.412 0.785 1.589 2.077 3.005 1.177 1.757 0.369 0.860 µs 7.611 25.68

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 -87.875 -87.097 -85.815 -61.584 -39.917 -38.971 -37.796 45.898 48.126 16.496 -61.239 ppb -118.9 629.3
Local Clock Time Offset -2.726 -1.759 -1.289 -0.017 0.867 1.274 2.764 2.156 3.033 0.649 -0.071 µs -5.099 14.28
Local RMS Frequency Jitter 171.000 190.000 219.000 298.000 446.000 557.000 663.000 227.000 367.000 72.411 311.874 10e-12 47.23 205.5
Local RMS Time Jitter 0.418 0.480 0.551 0.800 1.151 1.340 1.723 0.600 0.860 0.186 0.824 µs 51.4 222.2
Server Jitter 15.204.249.252 0.965 0.965 1.042 2.420 7.663 13.283 13.283 6.620 12.318 2.560 3.456 ms 3.11 11.24
Server Jitter 162.159.200.123 0.904 0.904 0.934 3.226 17.202 17.614 17.614 16.268 16.709 4.789 4.974 ms 1.638 4.559
Server Jitter 169.229.128.134 0.752 0.752 1.134 2.475 38.029 38.391 38.391 36.895 37.639 10.128 5.981 ms 1.482 5.469
Server Jitter 173.11.101.155 1.148 1.148 1.186 3.370 9.876 10.305 10.305 8.690 9.157 2.494 4.319 ms 3.473 8.923
Server Jitter 192.12.19.20 1.433 1.433 1.477 3.356 23.458 44.798 44.798 21.981 43.365 8.712 6.144 ms 2.354 10.18
Server Jitter 50.116.42.84 1.340 1.340 1.350 4.306 15.492 19.126 19.126 14.143 17.786 5.271 7.087 ms 1.702 3.527
Server Jitter 52.10.183.132 0.879 0.879 0.911 2.732 17.601 17.693 17.693 16.690 16.814 4.897 4.688 ms 1.566 4.282
Server Jitter 64.142.122.36 1.013 1.013 1.085 2.331 15.782 16.320 16.320 14.697 15.308 4.759 4.692 ms 1.287 3.028
Server Jitter 66.220.9.122 0.690 0.690 0.796 2.700 13.825 14.011 14.011 13.029 13.321 4.403 4.353 ms 1.201 2.783
Server Jitter SHM(0) 0.072 0.091 0.120 0.306 0.970 1.303 1.763 0.851 1.212 0.274 0.399 ms 2.913 9.137
Server Jitter SHM(1) 0.183 0.320 0.412 0.785 1.589 2.077 3.005 1.177 1.757 0.369 0.860 µs 7.611 25.68
Server Offset 15.204.249.252 4.068 4.068 4.088 5.328 6.937 7.838 7.838 2.849 3.771 1.030 5.573 ms 99.13 499.7
Server Offset 162.159.200.123 0.337 0.337 0.371 1.494 3.124 3.457 3.457 2.753 3.120 0.691 1.466 ms 5.953 19.05
Server Offset 169.229.128.134 1.230 1.230 1.501 2.377 2.834 2.901 2.901 1.333 1.672 0.365 2.345 ms 175.1 1026
Server Offset 173.11.101.155 -3.769 -3.769 -3.444 -1.859 1.447 1.804 1.804 4.891 5.574 1.430 -1.581 ms -14.98 43.27
Server Offset 192.12.19.20 1.710 1.710 1.759 2.507 3.464 4.081 4.081 1.705 2.371 0.483 2.520 ms 88.57 444.8
Server Offset 50.116.42.84 0.785 0.785 0.922 2.285 3.996 4.228 4.228 3.074 3.442 0.875 2.520 ms 12.47 37.17
Server Offset 52.10.183.132 2.595 2.595 3.208 4.113 6.399 6.411 6.411 3.192 3.816 0.838 4.278 ms 82.37 403.8
Server Offset 64.142.122.36 1.205 1.205 1.361 2.149 3.985 4.311 4.311 2.624 3.106 0.559 2.201 ms 36.26 160.4
Server Offset 66.220.9.122 1.674 1.674 1.877 2.354 3.049 3.227 3.227 1.172 1.553 0.359 2.363 ms 190.8 1169
Server Offset SHM(0) -98.594 -98.201 -97.684 -96.545 -95.170 -94.711 -93.998 2.514 3.490 0.801 -96.486 ms -1.793e+06 2.179e+08
Server Offset SHM(1) -2.727 -1.760 -1.290 -0.018 0.868 1.275 2.765 2.158 3.035 0.650 -0.071 µs -5.097 14.27
TDOP 0.630 0.630 0.690 0.890 1.180 1.280 1.590 0.490 0.650 0.167 0.877 91.02 457.9
Temp ZONE0 48.850 48.850 49.388 49.388 49.926 50.464 50.464 0.538 1.614 0.270 49.479 °C
nSats 7.000 8.000 8.000 9.000 10.000 11.000 11.000 2.000 3.000 0.700 9.274 nSat 1878 2.347e+04
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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