NTPsec

A-ntpsec-72-hour-stats

Report generated: Sat May 28 16:03:39 2022 UTC
Start Time: Wed May 25 16:03:38 2022 UTC
End Time: Sat May 28 16:03:38 2022 UTC
Report published: Sat May 28 09:03:52 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 -1,704.000 -960.000 -692.000 -1.000 691.000 973.000 1,815.000 1,383.000 1,933.000 418.884 -3.763 ns -4.031 10.05
Local Clock Frequency Offset -101.608 -99.838 -94.696 -63.507 -43.777 -39.688 -37.277 50.919 60.150 16.515 -67.084 ppb -145.2 819.1

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 217.000 306.000 354.000 508.000 702.000 798.000 1,116.000 348.000 492.000 106.396 514.961 ns 68.65 317.1

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 50.000 63.000 71.000 98.000 139.000 167.000 238.000 68.000 104.000 21.409 100.449 10e-12 62.48 289.2

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 -1,704.000 -960.000 -692.000 -1.000 691.000 973.000 1,815.000 1,383.000 1,933.000 418.884 -3.763 ns -4.031 10.05

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 -101.608 -99.838 -94.696 -63.507 -43.777 -39.688 -37.277 50.919 60.150 16.515 -67.084 ppb -145.2 819.1
Temp ZONE0 51.540 51.540 52.078 53.154 57.458 57.996 57.996 5.380 6.456 1.628 53.766 °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 1.013 9.521 nSat 616.7 5392
TDOP 0.490 0.540 0.600 0.820 1.400 1.600 3.150 0.800 1.060 0.242 0.873 27.07 110.3

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 162.159.200.1

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 4.413 4.582 4.800 5.092 5.402 6.301 10.754 0.602 1.719 0.390 5.124 ms 1827 2.3e+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 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 1.029 2.067 2.217 2.435 2.681 3.489 7.299 0.464 1.421 0.347 2.460 ms 252.3 1911

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 -2.684 -1.942 -1.013 -0.049 0.518 2.367 5.307 1.531 4.309 0.653 -0.073 ms -2.427 19.32

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 192.168.1.11

peer offset 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.11 -223.951 -139.840 -119.704 -56.005 17.986 35.638 257.111 137.690 175.478 44.532 -53.112 µs -16.71 52.67

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 192.168.1.12

peer offset 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.12 -228.042 -179.771 -157.951 -77.679 19.940 61.079 135.575 177.891 240.850 53.758 -70.558 µs -19.01 60.91

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 3.180 3.992 4.259 5.658 9.630 9.827 10.042 5.371 5.835 1.280 5.977 ms 62.35 296.9

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 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 3.680 4.055 4.310 5.833 7.787 10.123 14.117 3.478 6.068 1.278 6.358 ms 75.35 359

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 0.993 1.140 1.393 1.709 2.041 2.195 3.235 0.648 1.055 0.229 1.707 ms 290.4 2035

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 2.069 2.274 2.383 2.591 2.861 3.102 6.097 0.478 0.828 0.261 2.617 ms 774.3 7516

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 1.986 2.220 2.372 2.564 2.784 2.904 10.090 0.412 0.683 0.414 2.599 ms 175.9 1438

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) -59.842 -55.599 -54.000 -48.960 -44.626 -43.177 -40.163 9.374 12.422 2.815 -49.107 ms -6329 1.178e+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) -1,705.000 -961.000 -693.000 -2.000 692.000 974.000 1,816.000 1,385.000 1,935.000 419.677 -3.767 ns -4.031 10.04

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 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 162.159.200.1

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 0.067 0.148 0.203 0.725 5.578 17.648 20.645 5.375 17.500 2.901 1.503 ms 2.907 17.19

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 0.104 0.121 0.204 0.835 6.672 18.069 129.548 6.468 17.948 5.241 1.705 ms 14.71 355.3

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 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 0.280 0.654 0.901 1.595 6.370 17.995 32.152 5.469 17.341 3.225 2.356 ms 4.453 30.94

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 192.168.1.11

peer jitter 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.11 10.164 24.183 41.050 107.392 574.705 822.692 2,812.386 533.655 798.509 193.503 168.245 µs 4.299 39.86

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 192.168.1.12

peer jitter 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.12 0.017 0.027 0.045 0.115 0.628 0.874 5.189 0.583 0.847 0.219 0.180 ms 7.778 149.1

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 0.104 0.144 0.204 0.841 6.888 20.046 193.243 6.683 19.902 9.972 2.282 ms 13.07 250.4

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 0.093 0.155 0.214 0.744 8.660 17.861 54.693 8.446 17.706 4.249 1.797 ms 4.492 49.32

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 0.167 0.182 0.227 0.699 4.305 14.647 16.476 4.078 14.465 2.300 1.275 ms 3.404 20.42

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 0.094 0.142 0.238 1.025 2.275 12.714 23.400 2.037 12.572 2.180 1.376 ms 5.141 42.34

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 0.091 0.170 0.227 0.978 4.665 17.834 38.207 4.438 17.664 2.892 1.536 ms 5.154 51.9

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 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) 0.049 0.149 0.264 0.859 2.250 3.107 5.565 1.986 2.958 0.632 1.006 ms 3.36 11.14

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) 0.086 0.190 0.259 0.473 0.890 1.124 1.695 0.631 0.934 0.198 0.511 µs 9.887 33.34

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.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -101.608 -99.838 -94.696 -63.507 -43.777 -39.688 -37.277 50.919 60.150 16.515 -67.084 ppb -145.2 819.1
Local Clock Time Offset -1,704.000 -960.000 -692.000 -1.000 691.000 973.000 1,815.000 1,383.000 1,933.000 418.884 -3.763 ns -4.031 10.05
Local RMS Frequency Jitter 50.000 63.000 71.000 98.000 139.000 167.000 238.000 68.000 104.000 21.409 100.449 10e-12 62.48 289.2
Local RMS Time Jitter 217.000 306.000 354.000 508.000 702.000 798.000 1,116.000 348.000 492.000 106.396 514.961 ns 68.65 317.1
Server Jitter 162.159.200.1 0.067 0.148 0.203 0.725 5.578 17.648 20.645 5.375 17.500 2.901 1.503 ms 2.907 17.19
Server Jitter 169.229.128.134 0.104 0.121 0.204 0.835 6.672 18.069 129.548 6.468 17.948 5.241 1.705 ms 14.71 355.3
Server Jitter 173.11.101.155 0.280 0.654 0.901 1.595 6.370 17.995 32.152 5.469 17.341 3.225 2.356 ms 4.453 30.94
Server Jitter 192.168.1.11 10.164 24.183 41.050 107.392 574.705 822.692 2,812.386 533.655 798.509 193.503 168.245 µs 4.299 39.86
Server Jitter 192.168.1.12 0.017 0.027 0.045 0.115 0.628 0.874 5.189 0.583 0.847 0.219 0.180 ms 7.778 149.1
Server Jitter 194.58.207.79 0.104 0.144 0.204 0.841 6.888 20.046 193.243 6.683 19.902 9.972 2.282 ms 13.07 250.4
Server Jitter 194.58.207.80 0.093 0.155 0.214 0.744 8.660 17.861 54.693 8.446 17.706 4.249 1.797 ms 4.492 49.32
Server Jitter 204.17.205.24 0.167 0.182 0.227 0.699 4.305 14.647 16.476 4.078 14.465 2.300 1.275 ms 3.404 20.42
Server Jitter 216.218.192.202 0.094 0.142 0.238 1.025 2.275 12.714 23.400 2.037 12.572 2.180 1.376 ms 5.141 42.34
Server Jitter 216.218.254.202 0.091 0.170 0.227 0.978 4.665 17.834 38.207 4.438 17.664 2.892 1.536 ms 5.154 51.9
Server Jitter SHM(0) 0.049 0.149 0.264 0.859 2.250 3.107 5.565 1.986 2.958 0.632 1.006 ms 3.36 11.14
Server Jitter SHM(1) 0.086 0.190 0.259 0.473 0.890 1.124 1.695 0.631 0.934 0.198 0.511 µs 9.887 33.34
Server Offset 162.159.200.1 4.413 4.582 4.800 5.092 5.402 6.301 10.754 0.602 1.719 0.390 5.124 ms 1827 2.3e+04
Server Offset 169.229.128.134 1.029 2.067 2.217 2.435 2.681 3.489 7.299 0.464 1.421 0.347 2.460 ms 252.3 1911
Server Offset 173.11.101.155 -2.684 -1.942 -1.013 -0.049 0.518 2.367 5.307 1.531 4.309 0.653 -0.073 ms -2.427 19.32
Server Offset 192.168.1.11 -223.951 -139.840 -119.704 -56.005 17.986 35.638 257.111 137.690 175.478 44.532 -53.112 µs -16.71 52.67
Server Offset 192.168.1.12 -228.042 -179.771 -157.951 -77.679 19.940 61.079 135.575 177.891 240.850 53.758 -70.558 µs -19.01 60.91
Server Offset 194.58.207.79 3.180 3.992 4.259 5.658 9.630 9.827 10.042 5.371 5.835 1.280 5.977 ms 62.35 296.9
Server Offset 194.58.207.80 3.680 4.055 4.310 5.833 7.787 10.123 14.117 3.478 6.068 1.278 6.358 ms 75.35 359
Server Offset 204.17.205.24 0.993 1.140 1.393 1.709 2.041 2.195 3.235 0.648 1.055 0.229 1.707 ms 290.4 2035
Server Offset 216.218.192.202 2.069 2.274 2.383 2.591 2.861 3.102 6.097 0.478 0.828 0.261 2.617 ms 774.3 7516
Server Offset 216.218.254.202 1.986 2.220 2.372 2.564 2.784 2.904 10.090 0.412 0.683 0.414 2.599 ms 175.9 1438
Server Offset SHM(0) -59.842 -55.599 -54.000 -48.960 -44.626 -43.177 -40.163 9.374 12.422 2.815 -49.107 ms -6329 1.178e+05
Server Offset SHM(1) -1,705.000 -961.000 -693.000 -2.000 692.000 974.000 1,816.000 1,385.000 1,935.000 419.677 -3.767 ns -4.031 10.04
TDOP 0.490 0.540 0.600 0.820 1.400 1.600 3.150 0.800 1.060 0.242 0.873 27.07 110.3
Temp ZONE0 51.540 51.540 52.078 53.154 57.458 57.996 57.996 5.380 6.456 1.628 53.766 °C
nSats 6.000 7.000 8.000 10.000 11.000 12.000 12.000 3.000 5.000 1.013 9.521 nSat 616.7 5392
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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