NTPsec

B-ntpsec-6-hour-stats

Report generated: Wed Oct 23 20:05:53 2019 UTC
Start Time: Wed Oct 23 14:05:50 2019 UTC
End Time: Wed Oct 23 20:05:50 2019 UTC
Report published: Wed Oct 23 13:06:11 2019 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 -751.000 -478.000 -355.000 25.000 359.000 504.000 637.000 714.000 982.000 216.474 17.754 ns -3.647 8.994
Local Clock Frequency Offset -5.704 -5.704 -5.704 -5.697 -5.692 -5.691 -5.690 0.0119 0.0133 0.0035 -5.697 ppm -4.225e+09 6.831e+12

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 122.000 138.000 165.000 252.000 357.000 412.000 449.000 192.000 274.000 59.297 254.802 ns 46.09 191

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 28.000 32.000 37.000 51.000 72.000 81.000 98.000 35.000 49.000 10.756 52.554 10e-12 70.9 330.5

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 -751.000 -478.000 -355.000 25.000 359.000 504.000 637.000 714.000 982.000 216.474 17.754 ns -3.647 8.994

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 -5.704 -5.704 -5.704 -5.697 -5.692 -5.691 -5.690 0.0119 0.0133 0.0035 -5.697 ppm -4.225e+09 6.831e+12
Temp ZONE0 59.072 59.072 59.072 59.610 60.148 60.148 60.148 1.076 1.076 0.458 59.707 °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 12.000 4.000 4.000 1.062 9.253 nSat 482.2 3897
TDOP 0.500 0.580 0.600 0.820 1.450 1.890 2.070 0.850 1.310 0.280 0.925 20.39 75.67

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 2.060 2.060 2.060 2.311 3.850 3.850 3.850 1.790 1.790 0.551 2.527 ms 58.48 269.1

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 1.640 1.640 1.837 2.304 2.724 3.174 3.174 0.887 1.534 0.298 2.336 ms 341.8 2486

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 0.322 0.322 0.322 3.270 8.888 8.888 8.888 8.566 8.566 2.215 3.567 ms 2.802 7.347

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 -145.926 -20.564 49.350 124.909 230.726 379.026 472.224 181.376 399.590 66.830 131.719 µs 4.995 19.69

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 2.145 2.145 2.340 3.258 5.342 5.728 5.728 3.001 3.583 0.939 3.534 ms 30.21 115.3

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 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 0.979 0.979 1.418 1.986 2.542 2.785 2.785 1.124 1.807 0.360 1.950 ms 99.37 498.3

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 66.220.9.122

peer offset 66.220.9.122 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 66.220.9.122 2.068 2.068 2.206 2.778 3.427 3.549 3.549 1.221 1.481 0.327 2.779 ms 445.1 3517

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 76.14.161.109

peer offset 76.14.161.109 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 76.14.161.109 -2.922 -2.922 -1.845 -0.453 0.843 2.078 2.078 2.688 4.999 0.887 -0.428 ms -7.666 21.62

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(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) -458.324 -414.650 -395.527 -363.398 -326.046 -313.723 -290.206 69.480 100.927 21.375 -362.709 ms -5855 1.062e+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 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) -752.000 -479.000 -356.000 25.000 360.000 505.000 638.000 716.000 984.000 217.244 17.842 ns -3.647 8.981

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Jitters

peer jitters plot

The RMS Jitter of all refclocks and servers. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 104.131.155.175

peer jitter 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 104.131.155.175 0.000 0.000 0.000 0.739 3.280 3.280 3.280 3.280 3.280 0.993 0.941 ms 1.053 3.489

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 0.482 0.482 0.688 1.530 4.645 106.521 106.521 3.956 106.039 15.572 4.477 ms 3.199 21.59

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 1.898 1.898 1.898 4.232 5.983 5.983 5.983 4.085 4.085 1.221 4.064 ms 19.25 60.92

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 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 0.033 0.084 0.148 0.721 75.528 77.320 77.351 75.380 77.235 22.674 8.972 ms 0.4712 3.659

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 0.496 0.496 0.695 2.657 75.936 76.280 76.280 75.241 75.784 17.165 7.491 ms 1.813 8.536

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 0.503 0.503 0.588 2.538 10.949 75.798 75.798 10.361 75.295 8.845 4.016 ms 5.636 45.9

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 0.284 0.284 0.408 1.854 6.644 19.670 19.670 6.235 19.386 2.766 2.685 ms 3.399 20.07

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 76.14.161.109

peer jitter 76.14.161.109 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 76.14.161.109 1.544 1.544 1.865 22.228 134.949 152.144 152.144 133.084 150.601 40.717 37.275 ms 1.108 3.315

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) 1.866 4.528 6.115 11.641 22.885 30.102 48.956 16.770 25.574 5.372 12.745 ms 8.096 28.91

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) 48.000 90.000 112.000 227.000 441.000 551.000 678.000 329.000 461.000 98.791 244.650 ns 8.681 28.35

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 -5.704 -5.704 -5.704 -5.697 -5.692 -5.691 -5.690 0.0119 0.0133 0.0035 -5.697 ppm -4.225e+09 6.831e+12
Local Clock Time Offset -751.000 -478.000 -355.000 25.000 359.000 504.000 637.000 714.000 982.000 216.474 17.754 ns -3.647 8.994
Local RMS Frequency Jitter 28.000 32.000 37.000 51.000 72.000 81.000 98.000 35.000 49.000 10.756 52.554 10e-12 70.9 330.5
Local RMS Time Jitter 122.000 138.000 165.000 252.000 357.000 412.000 449.000 192.000 274.000 59.297 254.802 ns 46.09 191
Server Jitter 104.131.155.175 0.000 0.000 0.000 0.739 3.280 3.280 3.280 3.280 3.280 0.993 0.941 ms 1.053 3.489
Server Jitter 169.229.128.134 0.482 0.482 0.688 1.530 4.645 106.521 106.521 3.956 106.039 15.572 4.477 ms 3.199 21.59
Server Jitter 178.62.68.79 1.898 1.898 1.898 4.232 5.983 5.983 5.983 4.085 4.085 1.221 4.064 ms 19.25 60.92
Server Jitter 192.168.1.10 0.033 0.084 0.148 0.721 75.528 77.320 77.351 75.380 77.235 22.674 8.972 ms 0.4712 3.659
Server Jitter 203.123.48.219 0.496 0.496 0.695 2.657 75.936 76.280 76.280 75.241 75.784 17.165 7.491 ms 1.813 8.536
Server Jitter 204.17.205.24 0.503 0.503 0.588 2.538 10.949 75.798 75.798 10.361 75.295 8.845 4.016 ms 5.636 45.9
Server Jitter 66.220.9.122 0.284 0.284 0.408 1.854 6.644 19.670 19.670 6.235 19.386 2.766 2.685 ms 3.399 20.07
Server Jitter 76.14.161.109 1.544 1.544 1.865 22.228 134.949 152.144 152.144 133.084 150.601 40.717 37.275 ms 1.108 3.315
Server Jitter SHM(0) 1.866 4.528 6.115 11.641 22.885 30.102 48.956 16.770 25.574 5.372 12.745 ms 8.096 28.91
Server Jitter SHM(1) 48.000 90.000 112.000 227.000 441.000 551.000 678.000 329.000 461.000 98.791 244.650 ns 8.681 28.35
Server Offset 104.131.155.175 2.060 2.060 2.060 2.311 3.850 3.850 3.850 1.790 1.790 0.551 2.527 ms 58.48 269.1
Server Offset 169.229.128.134 1.640 1.640 1.837 2.304 2.724 3.174 3.174 0.887 1.534 0.298 2.336 ms 341.8 2486
Server Offset 178.62.68.79 0.322 0.322 0.322 3.270 8.888 8.888 8.888 8.566 8.566 2.215 3.567 ms 2.802 7.347
Server Offset 192.168.1.10 -145.926 -20.564 49.350 124.909 230.726 379.026 472.224 181.376 399.590 66.830 131.719 µs 4.995 19.69
Server Offset 203.123.48.219 2.145 2.145 2.340 3.258 5.342 5.728 5.728 3.001 3.583 0.939 3.534 ms 30.21 115.3
Server Offset 204.17.205.24 0.979 0.979 1.418 1.986 2.542 2.785 2.785 1.124 1.807 0.360 1.950 ms 99.37 498.3
Server Offset 66.220.9.122 2.068 2.068 2.206 2.778 3.427 3.549 3.549 1.221 1.481 0.327 2.779 ms 445.1 3517
Server Offset 76.14.161.109 -2.922 -2.922 -1.845 -0.453 0.843 2.078 2.078 2.688 4.999 0.887 -0.428 ms -7.666 21.62
Server Offset SHM(0) -458.324 -414.650 -395.527 -363.398 -326.046 -313.723 -290.206 69.480 100.927 21.375 -362.709 ms -5855 1.062e+05
Server Offset SHM(1) -752.000 -479.000 -356.000 25.000 360.000 505.000 638.000 716.000 984.000 217.244 17.842 ns -3.647 8.981
TDOP 0.500 0.580 0.600 0.820 1.450 1.890 2.070 0.850 1.310 0.280 0.925 20.39 75.67
Temp ZONE0 59.072 59.072 59.072 59.610 60.148 60.148 60.148 1.076 1.076 0.458 59.707 °C
nSats 7.000 7.000 7.000 9.000 11.000 11.000 12.000 4.000 4.000 1.062 9.253 nSat 482.2 3897
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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