NTPsec

ntp2.wiktel.com

Report generated: Wed Nov 30 10:53:01 2022 UTC
Start Time: Tue Nov 29 10:53:00 2022 UTC
End Time: Wed Nov 30 10:53:00 2022 UTC
Report Period: 1.0 days

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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 -19.538 -9.125 -5.478 0.373 3.283 4.582 9.096 8.761 13.707 2.608 0.004 µs -5.565 20.56
Local Clock Frequency Offset -14.232 -14.075 -13.771 -12.811 -12.147 -12.047 -12.006 1.624 2.028 0.476 -12.850 ppm -2.209e+04 6.214e+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 0.572 1.017 1.350 2.882 5.255 6.528 11.380 3.905 5.511 1.229 3.041 µs 8.42 26.32

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 1.010 1.854 2.418 4.622 7.764 9.472 14.812 5.346 7.618 1.679 4.811 ppb 12.78 41.8

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 -19.538 -9.125 -5.478 0.373 3.283 4.582 9.096 8.761 13.707 2.608 0.004 µs -5.565 20.56

The clock offsets of the local clock as a histogram.

The Local Clock Offset is field 3 from the loopstats 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 6.000 7.000 9.000 11.000 12.000 12.000 4.000 6.000 1.312 8.864 nSat 208.4 1306
TDOP 0.520 0.550 0.600 0.820 1.330 1.800 1.970 0.730 1.250 0.234 0.892 32.07 130.1

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 132.163.97.5

peer offset 132.163.97.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 132.163.97.5 1.707 1.712 1.720 1.760 1.812 3.515 3.565 0.092 1.803 0.280 1.805 ms 183.4 1220

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 132.246.11.237

peer offset 132.246.11.237 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 132.246.11.237 -4.311 -0.336 0.662 0.735 0.802 3.329 3.336 0.140 3.665 0.720 0.774 ms -1.493 29.8

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 134.84.84.84

peer offset 134.84.84.84 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 134.84.84.84 -0.360 -0.120 -0.075 0.013 0.108 1.792 2.278 0.183 1.911 0.348 0.076 ms 1.832 13.03

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 204.9.54.119

peer offset 204.9.54.119 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.9.54.119 -0.499 -0.496 -0.488 -0.465 -0.447 3.531 3.534 0.042 4.027 0.844 -0.280 ms -2.076 10.31

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 2600:2600::99 (ntp1.wiktel.com)

peer offset 2600:2600::99 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2600:2600::99 (ntp1.wiktel.com) -64.549 -63.733 -57.945 -43.035 -29.940 -23.987 -22.789 28.005 39.746 8.756 -43.478 µs -230.3 1484

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 2602:fd53:11e:123::1 (time1.mbix.ca)

peer offset 2602:fd53:11e:123::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2602:fd53:11e:123::1 (time1.mbix.ca) -0.553 -0.508 -0.339 2.972 3.299 3.386 3.412 3.637 3.895 0.836 2.729 ms 15.28 40.93

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 2606:4700:f1::1 (time.cloudflare.com)

peer offset 2606:4700:f1::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2606:4700:f1::1 (time.cloudflare.com) 0.675 1.095 1.135 1.229 1.814 2.927 2.937 0.679 1.832 0.321 1.302 ms 41.97 215.9

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 2607:f128::50

peer offset 2607:f128::50 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2607:f128::50 -157.500 -130.522 288.375 342.901 378.455 394.968 402.252 90.080 525.490 99.211 322.940 µs 14.2 38.22

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 2607:f388::123:2 (ntp2.doit.wisc.edu)

peer offset 2607:f388::123:2 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2607:f388::123:2 (ntp2.doit.wisc.edu) -536.878 -532.516 -501.058 -56.607 -37.664 -28.168 -24.882 463.394 504.348 102.588 -79.911 µs -14.96 74.62

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 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) -19.539 -9.125 -5.479 0.374 3.284 4.583 9.097 8.763 13.708 2.609 0.004 µs -5.564 20.56

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 132.163.97.5

peer jitter 132.163.97.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 132.163.97.5 0.000 0.000 0.000 0.028 0.073 1.728 1.751 0.073 1.728 0.271 0.078 ms 2.887 18.87

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 132.246.11.237

peer jitter 132.246.11.237 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 132.246.11.237 0.010 0.015 0.020 0.316 137.072 180.217 187.059 137.052 180.202 43.752 18.525 ms 0.6108 4.619

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 134.84.84.84

peer jitter 134.84.84.84 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 134.84.84.84 0.003 0.004 0.005 0.015 0.053 1.260 1.792 0.048 1.256 0.186 0.045 ms 4.484 37.83

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 204.9.54.119

peer jitter 204.9.54.119 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.9.54.119 9.761 14.735 20.626 41.053 59.617 66.893 3,990.146 38.991 52.158 321.626 66.854 µs 9.187 112.6

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 2600:2600::99 (ntp1.wiktel.com)

peer jitter 2600:2600::99 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2600:2600::99 (ntp1.wiktel.com) 5.069 6.865 8.363 17.064 29.944 37.229 145.176 21.581 30.364 10.047 18.410 µs 10.28 118.7

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 2602:fd53:11e:123::1 (time1.mbix.ca)

peer jitter 2602:fd53:11e:123::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2602:fd53:11e:123::1 (time1.mbix.ca) 0.005 0.008 0.012 0.029 0.078 3.067 3.386 0.066 3.059 0.344 0.073 ms 5.902 56.05

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 2606:4700:f1::1 (time.cloudflare.com)

peer jitter 2606:4700:f1::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2606:4700:f1::1 (time.cloudflare.com) 0.006 0.008 0.012 0.034 0.297 2.047 2.062 0.286 2.040 0.285 0.097 ms 3.197 21.74

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 2607:f128::50

peer jitter 2607:f128::50 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2607:f128::50 9.518 10.379 13.836 29.611 64.013 370.405 869.321 50.177 360.026 75.526 40.580 µs 7.391 74.3

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 2607:f388::123:2 (ntp2.doit.wisc.edu)

peer jitter 2607:f388::123:2 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2607:f388::123:2 (ntp2.doit.wisc.edu) 0.004 0.007 0.011 0.738 13.498 16.467 18.594 13.487 16.461 4.246 3.131 ms 0.6943 3.215

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) 0.132 0.436 0.711 2.416 6.757 9.495 19.067 6.046 9.059 1.985 2.884 µs 3.033 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.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -14.232 -14.075 -13.771 -12.811 -12.147 -12.047 -12.006 1.624 2.028 0.476 -12.850 ppm -2.209e+04 6.214e+05
Local Clock Time Offset -19.538 -9.125 -5.478 0.373 3.283 4.582 9.096 8.761 13.707 2.608 0.004 µs -5.565 20.56
Local RMS Frequency Jitter 1.010 1.854 2.418 4.622 7.764 9.472 14.812 5.346 7.618 1.679 4.811 ppb 12.78 41.8
Local RMS Time Jitter 0.572 1.017 1.350 2.882 5.255 6.528 11.380 3.905 5.511 1.229 3.041 µs 8.42 26.32
Server Jitter 132.163.97.5 0.000 0.000 0.000 0.028 0.073 1.728 1.751 0.073 1.728 0.271 0.078 ms 2.887 18.87
Server Jitter 132.246.11.237 0.010 0.015 0.020 0.316 137.072 180.217 187.059 137.052 180.202 43.752 18.525 ms 0.6108 4.619
Server Jitter 134.84.84.84 0.003 0.004 0.005 0.015 0.053 1.260 1.792 0.048 1.256 0.186 0.045 ms 4.484 37.83
Server Jitter 204.9.54.119 9.761 14.735 20.626 41.053 59.617 66.893 3,990.146 38.991 52.158 321.626 66.854 µs 9.187 112.6
Server Jitter 2600:2600::99 (ntp1.wiktel.com) 5.069 6.865 8.363 17.064 29.944 37.229 145.176 21.581 30.364 10.047 18.410 µs 10.28 118.7
Server Jitter 2602:fd53:11e:123::1 (time1.mbix.ca) 0.005 0.008 0.012 0.029 0.078 3.067 3.386 0.066 3.059 0.344 0.073 ms 5.902 56.05
Server Jitter 2606:4700:f1::1 (time.cloudflare.com) 0.006 0.008 0.012 0.034 0.297 2.047 2.062 0.286 2.040 0.285 0.097 ms 3.197 21.74
Server Jitter 2607:f128::50 9.518 10.379 13.836 29.611 64.013 370.405 869.321 50.177 360.026 75.526 40.580 µs 7.391 74.3
Server Jitter 2607:f388::123:2 (ntp2.doit.wisc.edu) 0.004 0.007 0.011 0.738 13.498 16.467 18.594 13.487 16.461 4.246 3.131 ms 0.6943 3.215
Server Jitter SHM(1) 0.132 0.436 0.711 2.416 6.757 9.495 19.067 6.046 9.059 1.985 2.884 µs 3.033 11.24
Server Offset 132.163.97.5 1.707 1.712 1.720 1.760 1.812 3.515 3.565 0.092 1.803 0.280 1.805 ms 183.4 1220
Server Offset 132.246.11.237 -4.311 -0.336 0.662 0.735 0.802 3.329 3.336 0.140 3.665 0.720 0.774 ms -1.493 29.8
Server Offset 134.84.84.84 -0.360 -0.120 -0.075 0.013 0.108 1.792 2.278 0.183 1.911 0.348 0.076 ms 1.832 13.03
Server Offset 204.9.54.119 -0.499 -0.496 -0.488 -0.465 -0.447 3.531 3.534 0.042 4.027 0.844 -0.280 ms -2.076 10.31
Server Offset 2600:2600::99 (ntp1.wiktel.com) -64.549 -63.733 -57.945 -43.035 -29.940 -23.987 -22.789 28.005 39.746 8.756 -43.478 µs -230.3 1484
Server Offset 2602:fd53:11e:123::1 (time1.mbix.ca) -0.553 -0.508 -0.339 2.972 3.299 3.386 3.412 3.637 3.895 0.836 2.729 ms 15.28 40.93
Server Offset 2606:4700:f1::1 (time.cloudflare.com) 0.675 1.095 1.135 1.229 1.814 2.927 2.937 0.679 1.832 0.321 1.302 ms 41.97 215.9
Server Offset 2607:f128::50 -157.500 -130.522 288.375 342.901 378.455 394.968 402.252 90.080 525.490 99.211 322.940 µs 14.2 38.22
Server Offset 2607:f388::123:2 (ntp2.doit.wisc.edu) -536.878 -532.516 -501.058 -56.607 -37.664 -28.168 -24.882 463.394 504.348 102.588 -79.911 µs -14.96 74.62
Server Offset SHM(1) -19.539 -9.125 -5.479 0.374 3.284 4.583 9.097 8.763 13.708 2.609 0.004 µs -5.564 20.56
TDOP 0.520 0.550 0.600 0.820 1.330 1.800 1.970 0.730 1.250 0.234 0.892 32.07 130.1
nSats 5.000 6.000 7.000 9.000 11.000 12.000 12.000 4.000 6.000 1.312 8.864 nSat 208.4 1306
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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