NTPsec

A-ntpsec-72-hour-stats

Report generated: Tue May 20 05:09:45 2025 UTC
Start Time: Sat May 17 05:09:43 2025 UTC
End Time: Tue May 20 05:09:43 2025 UTC
Report published: Mon May 19 10:10:11 PM 2025 PDT
Report Period: 3.0 days

Local Clock Time/Frequency Offsets

local offset plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Time Offset -3.097 -1.883 -1.254 0.054 1.099 1.537 3.725 2.353 3.420 0.715 0.007 µs -4.299 11.66
Local Clock Frequency Offset -393.326 -381.668 -358.734 -218.933 -76.355 -41.275 -37.796 282.379 340.393 85.744 -221.511 ppb -56.73 243.6

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 0.361 0.511 0.604 0.885 1.271 1.468 2.300 0.667 0.957 0.205 0.904 µs 50.9 219.1

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 134.000 200.000 235.000 335.000 469.000 542.000 1,174.000 234.000 342.000 73.989 341.575 10e-12 59.06 269.6

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 -3.097 -1.883 -1.254 0.054 1.099 1.537 3.725 2.353 3.420 0.715 0.007 µs -4.299 11.66

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 -393.326 -381.668 -358.734 -218.933 -76.355 -41.275 -37.796 282.379 340.393 85.744 -221.511 ppb -56.73 243.6
Temp ZONE0 45.622 45.622 46.160 47.774 49.388 49.926 50.464 3.228 4.304 0.976 47.569 °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 10.000 12.000 12.000 12.000 4.000 4.000 1.064 9.818 nSat 582.3 5005
TDOP 0.490 0.530 0.570 0.790 1.220 1.420 1.620 0.650 0.890 0.200 0.829 41.45 172.7

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 -2.471 3.144 3.760 4.811 7.091 9.236 14.385 3.332 6.092 1.262 5.194 ms 40.98 180.5

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 -0.604 0.034 0.743 1.663 3.505 3.991 5.701 2.762 3.957 0.839 1.824 ms 6.161 20.02

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 -6.031 -0.736 0.191 1.138 3.115 5.759 8.481 2.924 6.495 1.130 1.279 ms 1.517 18.06

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 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 -1.901 0.810 1.622 2.380 3.752 5.458 9.569 2.129 4.648 0.728 2.454 ms 22.97 113.3

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 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 -9.277 -6.323 -4.364 -2.010 1.933 3.830 5.558 6.296 10.153 2.014 -1.686 ms -11.24 31.95

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 -0.644 1.008 1.873 2.583 3.904 6.186 9.974 2.031 5.177 0.767 2.651 ms 25.45 132

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 -1.060 0.408 1.203 2.062 4.010 5.666 9.376 2.807 5.257 0.957 2.274 ms 8.459 34.22

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 0.869 1.792 2.723 3.799 6.112 8.012 10.886 3.389 6.220 1.099 4.035 ms 28.81 120.7

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 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 -2.965 0.722 1.403 2.127 3.346 6.561 10.210 1.943 5.840 0.801 2.188 ms 14.09 83.46

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 -8.637 0.064 1.217 2.491 4.295 6.569 9.818 3.077 6.505 1.029 2.508 ms 7.35 43.29

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) -102.397 -100.856 -99.719 -96.959 -95.073 -94.501 -93.359 4.646 6.354 1.404 -97.144 ms -3.463e+05 2.433e+07

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) -3.098 -1.884 -1.255 0.055 1.100 1.538 3.726 2.355 3.422 0.716 0.007 µs -4.298 11.65

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 0.329 0.785 1.061 2.422 14.140 21.314 82.167 13.080 20.530 5.040 4.330 ms 5.031 65.21

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 0.481 0.787 1.125 2.503 14.824 21.047 25.572 13.699 20.259 4.448 4.313 ms 2.026 7.08

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 0.578 0.814 1.053 2.608 15.760 25.571 32.448 14.707 24.757 5.157 4.858 ms 2.02 8.291

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 0.360 0.677 0.934 2.384 15.988 25.790 38.391 15.054 25.113 5.431 4.670 ms 1.963 8.718

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 0.934 1.094 1.690 3.754 16.279 23.471 32.041 14.588 22.377 4.719 5.593 ms 2.488 8.388

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 0.258 0.473 0.831 2.558 25.239 35.265 50.444 24.407 34.791 8.364 6.624 ms 1.338 5.238

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 0.345 0.756 1.001 2.504 15.492 25.457 38.483 14.491 24.701 5.360 4.816 ms 2.049 8.888

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 0.267 0.745 1.044 2.377 15.690 21.615 47.864 14.646 20.870 5.086 4.581 ms 2.289 11.75

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 0.276 0.491 0.883 2.270 16.119 21.565 31.663 15.235 21.074 4.941 4.533 ms 1.657 5.721

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 0.144 0.711 0.947 2.500 14.348 25.977 32.512 13.401 25.267 4.827 4.419 ms 2.153 8.925

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) 0.037 0.080 0.114 0.328 1.024 1.442 2.897 0.910 1.362 0.302 0.421 ms 2.777 9.394

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) 0.140 0.325 0.442 0.866 1.700 2.232 4.783 1.258 1.907 0.397 0.942 µs 7.994 27.81

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 -393.326 -381.668 -358.734 -218.933 -76.355 -41.275 -37.796 282.379 340.393 85.744 -221.511 ppb -56.73 243.6
Local Clock Time Offset -3.097 -1.883 -1.254 0.054 1.099 1.537 3.725 2.353 3.420 0.715 0.007 µs -4.299 11.66
Local RMS Frequency Jitter 134.000 200.000 235.000 335.000 469.000 542.000 1,174.000 234.000 342.000 73.989 341.575 10e-12 59.06 269.6
Local RMS Time Jitter 0.361 0.511 0.604 0.885 1.271 1.468 2.300 0.667 0.957 0.205 0.904 µs 50.9 219.1
Server Jitter 15.204.249.252 0.329 0.785 1.061 2.422 14.140 21.314 82.167 13.080 20.530 5.040 4.330 ms 5.031 65.21
Server Jitter 162.159.200.1 0.481 0.787 1.125 2.503 14.824 21.047 25.572 13.699 20.259 4.448 4.313 ms 2.026 7.08
Server Jitter 162.159.200.123 0.578 0.814 1.053 2.608 15.760 25.571 32.448 14.707 24.757 5.157 4.858 ms 2.02 8.291
Server Jitter 169.229.128.134 0.360 0.677 0.934 2.384 15.988 25.790 38.391 15.054 25.113 5.431 4.670 ms 1.963 8.718
Server Jitter 173.11.101.155 0.934 1.094 1.690 3.754 16.279 23.471 32.041 14.588 22.377 4.719 5.593 ms 2.488 8.388
Server Jitter 192.12.19.20 0.258 0.473 0.831 2.558 25.239 35.265 50.444 24.407 34.791 8.364 6.624 ms 1.338 5.238
Server Jitter 50.116.42.84 0.345 0.756 1.001 2.504 15.492 25.457 38.483 14.491 24.701 5.360 4.816 ms 2.049 8.888
Server Jitter 52.10.183.132 0.267 0.745 1.044 2.377 15.690 21.615 47.864 14.646 20.870 5.086 4.581 ms 2.289 11.75
Server Jitter 64.142.122.36 0.276 0.491 0.883 2.270 16.119 21.565 31.663 15.235 21.074 4.941 4.533 ms 1.657 5.721
Server Jitter 66.220.9.122 0.144 0.711 0.947 2.500 14.348 25.977 32.512 13.401 25.267 4.827 4.419 ms 2.153 8.925
Server Jitter SHM(0) 0.037 0.080 0.114 0.328 1.024 1.442 2.897 0.910 1.362 0.302 0.421 ms 2.777 9.394
Server Jitter SHM(1) 0.140 0.325 0.442 0.866 1.700 2.232 4.783 1.258 1.907 0.397 0.942 µs 7.994 27.81
Server Offset 15.204.249.252 -2.471 3.144 3.760 4.811 7.091 9.236 14.385 3.332 6.092 1.262 5.194 ms 40.98 180.5
Server Offset 162.159.200.1 -0.604 0.034 0.743 1.663 3.505 3.991 5.701 2.762 3.957 0.839 1.824 ms 6.161 20.02
Server Offset 162.159.200.123 -6.031 -0.736 0.191 1.138 3.115 5.759 8.481 2.924 6.495 1.130 1.279 ms 1.517 18.06
Server Offset 169.229.128.134 -1.901 0.810 1.622 2.380 3.752 5.458 9.569 2.129 4.648 0.728 2.454 ms 22.97 113.3
Server Offset 173.11.101.155 -9.277 -6.323 -4.364 -2.010 1.933 3.830 5.558 6.296 10.153 2.014 -1.686 ms -11.24 31.95
Server Offset 192.12.19.20 -0.644 1.008 1.873 2.583 3.904 6.186 9.974 2.031 5.177 0.767 2.651 ms 25.45 132
Server Offset 50.116.42.84 -1.060 0.408 1.203 2.062 4.010 5.666 9.376 2.807 5.257 0.957 2.274 ms 8.459 34.22
Server Offset 52.10.183.132 0.869 1.792 2.723 3.799 6.112 8.012 10.886 3.389 6.220 1.099 4.035 ms 28.81 120.7
Server Offset 64.142.122.36 -2.965 0.722 1.403 2.127 3.346 6.561 10.210 1.943 5.840 0.801 2.188 ms 14.09 83.46
Server Offset 66.220.9.122 -8.637 0.064 1.217 2.491 4.295 6.569 9.818 3.077 6.505 1.029 2.508 ms 7.35 43.29
Server Offset SHM(0) -102.397 -100.856 -99.719 -96.959 -95.073 -94.501 -93.359 4.646 6.354 1.404 -97.144 ms -3.463e+05 2.433e+07
Server Offset SHM(1) -3.098 -1.884 -1.255 0.055 1.100 1.538 3.726 2.355 3.422 0.716 0.007 µs -4.298 11.65
TDOP 0.490 0.530 0.570 0.790 1.220 1.420 1.620 0.650 0.890 0.200 0.829 41.45 172.7
Temp ZONE0 45.622 45.622 46.160 47.774 49.388 49.926 50.464 3.228 4.304 0.976 47.569 °C
nSats 7.000 8.000 8.000 10.000 12.000 12.000 12.000 4.000 4.000 1.064 9.818 nSat 582.3 5005
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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