NTPsec

C-ntpsec-72-hour-stats

Report generated: Sat May 28 16:04:16 2022 UTC
Start Time: Wed May 25 16:04:14 2022 UTC
End Time: Sat May 28 16:04:14 2022 UTC
Report published: Sat May 28 09:04:26 2022 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 -2.968 -1.538 -1.093 -0.062 1.183 1.625 2.919 2.276 3.163 0.714 -0.010 µs -3.962 9.642
Local Clock Frequency Offset -6.954 -6.934 -6.911 -6.578 -5.815 -5.750 -5.738 1.097 1.184 0.327 -6.491 ppm -9138 1.919e+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 88.000 121.000 143.000 228.000 416.000 564.000 1,059.000 273.000 443.000 90.631 246.652 ns 12.1 48.24

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 25.000 48.000 65.000 204.000 626.000 908.000 1,316.000 561.000 860.000 180.800 253.914 10e-12 2.912 9.792

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 -2.968 -1.538 -1.093 -0.062 1.183 1.625 2.919 2.276 3.163 0.714 -0.010 µs -3.962 9.642

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 -6.954 -6.934 -6.911 -6.578 -5.815 -5.750 -5.738 1.097 1.184 0.327 -6.491 ppm -9138 1.919e+05
Temp ZONE0 45.084 46.160 46.160 47.774 51.540 52.078 52.616 5.380 5.918 1.534 48.134 °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 6.000 7.000 8.000 10.000 11.000 12.000 12.000 3.000 5.000 1.009 9.534 nSat 629 5536
TDOP 0.490 0.540 0.580 0.810 1.380 1.510 1.990 0.800 0.970 0.236 0.869 28.86 115.6

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 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 -8.154 4.604 4.967 5.287 5.666 6.179 8.037 0.699 1.575 0.983 5.228 ms 82.81 407.7

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 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 -11.469 2.007 2.401 2.624 2.950 4.162 11.093 0.549 2.156 0.862 2.638 ms 6.842 142.1

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 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 -10.014 -2.197 -1.147 0.075 0.724 2.188 5.172 1.870 4.385 0.782 0.001 ms -5.878 55.12

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 -137.586 110.513 157.556 232.543 300.959 310.931 368.189 143.403 200.418 47.948 237.856 µs 72.92 330.4

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 194.58.207.79

peer offset 194.58.207.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 194.58.207.79 -20.809 3.111 5.879 7.927 8.634 9.973 17.584 2.755 6.862 1.934 7.501 ms 24.19 129.6

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 194.58.207.80

peer offset 194.58.207.80 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 194.58.207.80 -17.411 5.076 5.717 7.740 9.982 10.232 15.089 4.264 5.157 1.767 7.244 ms 35.63 156.9

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 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 0.756 1.322 1.551 1.900 2.217 3.355 4.529 0.667 2.033 0.345 1.909 ms 110.7 646.4

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 216.218.192.202

peer offset 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.192.202 -2.489 2.248 2.566 2.767 3.057 4.980 6.573 0.491 2.733 0.426 2.808 ms 192.9 1269

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 216.218.254.202

peer offset 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.254.202 2.157 2.429 2.527 2.721 3.005 3.830 9.497 0.478 1.401 0.393 2.764 ms 249.3 2003

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) -69.044 -65.201 -62.812 -55.274 -48.598 -46.493 -43.119 14.214 18.708 4.329 -55.409 ms -2669 3.74e+04

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

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

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

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



Server Offset SHM(1)

peer offset SHM(1) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(1) -2.969 -1.539 -1.094 -0.063 1.184 1.626 2.920 2.278 3.165 0.715 -0.010 µs -3.963 9.638

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 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 0.083 0.168 0.273 3.385 28.876 36.784 189.950 28.604 36.616 13.190 9.617 ms 5.15 71.51

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 0.144 0.174 0.258 5.924 32.605 40.106 196.550 32.347 39.932 12.754 10.754 ms 3.468 48.79

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 0.460 0.585 0.907 2.984 27.060 39.480 191.176 26.153 38.895 14.170 9.713 ms 6.241 80.78

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 0.013 0.022 0.036 0.121 0.610 0.887 5.050 0.574 0.864 0.238 0.180 ms 9.044 165.1

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 194.58.207.79

peer jitter 194.58.207.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 194.58.207.79 0.070 0.173 0.269 8.323 33.068 193.745 213.302 32.799 193.572 26.446 14.007 ms 4.328 32.22

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 194.58.207.80

peer jitter 194.58.207.80 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 194.58.207.80 0.131 0.186 0.272 5.829 32.024 39.852 199.478 31.752 39.665 17.487 11.541 ms 5.486 60.3

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 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 0.175 0.191 0.347 3.688 24.835 28.625 35.075 24.488 28.434 8.494 8.201 ms 0.7139 2.368

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 216.218.192.202

peer jitter 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.192.202 0.077 0.170 0.274 7.226 34.244 191.866 211.050 33.969 191.696 25.216 13.334 ms 4.496 35.34

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 216.218.254.202

peer jitter 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.254.202 0.114 0.133 0.246 5.569 30.274 38.952 197.245 30.028 38.819 19.262 11.429 ms 5.563 55.53

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) 0.053 0.207 0.374 1.424 5.438 7.153 8.991 5.064 6.946 1.528 1.885 ms 2.398 7.708

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) 0.038 0.085 0.118 0.279 0.702 1.056 2.271 0.584 0.971 0.200 0.329 µs 4.23 18.16

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 -6.954 -6.934 -6.911 -6.578 -5.815 -5.750 -5.738 1.097 1.184 0.327 -6.491 ppm -9138 1.919e+05
Local Clock Time Offset -2.968 -1.538 -1.093 -0.062 1.183 1.625 2.919 2.276 3.163 0.714 -0.010 µs -3.962 9.642
Local RMS Frequency Jitter 25.000 48.000 65.000 204.000 626.000 908.000 1,316.000 561.000 860.000 180.800 253.914 10e-12 2.912 9.792
Local RMS Time Jitter 88.000 121.000 143.000 228.000 416.000 564.000 1,059.000 273.000 443.000 90.631 246.652 ns 12.1 48.24
Server Jitter 162.159.200.123 0.083 0.168 0.273 3.385 28.876 36.784 189.950 28.604 36.616 13.190 9.617 ms 5.15 71.51
Server Jitter 169.229.128.134 0.144 0.174 0.258 5.924 32.605 40.106 196.550 32.347 39.932 12.754 10.754 ms 3.468 48.79
Server Jitter 173.11.101.155 0.460 0.585 0.907 2.984 27.060 39.480 191.176 26.153 38.895 14.170 9.713 ms 6.241 80.78
Server Jitter 192.168.1.10 0.013 0.022 0.036 0.121 0.610 0.887 5.050 0.574 0.864 0.238 0.180 ms 9.044 165.1
Server Jitter 194.58.207.79 0.070 0.173 0.269 8.323 33.068 193.745 213.302 32.799 193.572 26.446 14.007 ms 4.328 32.22
Server Jitter 194.58.207.80 0.131 0.186 0.272 5.829 32.024 39.852 199.478 31.752 39.665 17.487 11.541 ms 5.486 60.3
Server Jitter 204.17.205.24 0.175 0.191 0.347 3.688 24.835 28.625 35.075 24.488 28.434 8.494 8.201 ms 0.7139 2.368
Server Jitter 216.218.192.202 0.077 0.170 0.274 7.226 34.244 191.866 211.050 33.969 191.696 25.216 13.334 ms 4.496 35.34
Server Jitter 216.218.254.202 0.114 0.133 0.246 5.569 30.274 38.952 197.245 30.028 38.819 19.262 11.429 ms 5.563 55.53
Server Jitter SHM(0) 0.053 0.207 0.374 1.424 5.438 7.153 8.991 5.064 6.946 1.528 1.885 ms 2.398 7.708
Server Jitter SHM(1) 0.038 0.085 0.118 0.279 0.702 1.056 2.271 0.584 0.971 0.200 0.329 µs 4.23 18.16
Server Offset 162.159.200.123 -8.154 4.604 4.967 5.287 5.666 6.179 8.037 0.699 1.575 0.983 5.228 ms 82.81 407.7
Server Offset 169.229.128.134 -11.469 2.007 2.401 2.624 2.950 4.162 11.093 0.549 2.156 0.862 2.638 ms 6.842 142.1
Server Offset 173.11.101.155 -10.014 -2.197 -1.147 0.075 0.724 2.188 5.172 1.870 4.385 0.782 0.001 ms -5.878 55.12
Server Offset 192.168.1.10 -137.586 110.513 157.556 232.543 300.959 310.931 368.189 143.403 200.418 47.948 237.856 µs 72.92 330.4
Server Offset 194.58.207.79 -20.809 3.111 5.879 7.927 8.634 9.973 17.584 2.755 6.862 1.934 7.501 ms 24.19 129.6
Server Offset 194.58.207.80 -17.411 5.076 5.717 7.740 9.982 10.232 15.089 4.264 5.157 1.767 7.244 ms 35.63 156.9
Server Offset 204.17.205.24 0.756 1.322 1.551 1.900 2.217 3.355 4.529 0.667 2.033 0.345 1.909 ms 110.7 646.4
Server Offset 216.218.192.202 -2.489 2.248 2.566 2.767 3.057 4.980 6.573 0.491 2.733 0.426 2.808 ms 192.9 1269
Server Offset 216.218.254.202 2.157 2.429 2.527 2.721 3.005 3.830 9.497 0.478 1.401 0.393 2.764 ms 249.3 2003
Server Offset SHM(0) -69.044 -65.201 -62.812 -55.274 -48.598 -46.493 -43.119 14.214 18.708 4.329 -55.409 ms -2669 3.74e+04
Server Offset SHM(1) -2.969 -1.539 -1.094 -0.063 1.184 1.626 2.920 2.278 3.165 0.715 -0.010 µs -3.963 9.638
TDOP 0.490 0.540 0.580 0.810 1.380 1.510 1.990 0.800 0.970 0.236 0.869 28.86 115.6
Temp ZONE0 45.084 46.160 46.160 47.774 51.540 52.078 52.616 5.380 5.918 1.534 48.134 °C
nSats 6.000 7.000 8.000 10.000 11.000 12.000 12.000 3.000 5.000 1.009 9.534 nSat 629 5536
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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