Arbiter Systems 1088A, Руководство по эксплуатации

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218 Options List
NTP Status Page
To view the NTP service, select NTP tab on the left and the Status tab above. Figure C.45
illustrates the status of NTP.
Option 34 Network Time Module
Status Configure
NTP
PTP
SNMP
Clock
Network
System
Support
Logout
Authentication
NTP
Root Dispersion
Offset
Frequency
System Jitter
Clock Jitter
Clock wander
Stratum
Running
0.420
-0.063
1.337
0.009
0.008
0.001
1
Figure C.45: NTP Status Page
NTP Terms
•
NTP: either running or stopped.
•
Root Dispersion: (or dispersion) represents the maximum error of the local clock relative to
the reference clock.
•
Offset: (or clock offset) represents the amount to adjust the local clock to bring it into
correspondence with the reference clock.
•
Frequency: frequency offset (PPM) relative to hardware clock.
•
System Jitter (psi): is defined as the root-mean-square (RMS) average of the most recent
offset differences, and it represents the nominal error in estimating the offset (of the system).
•
Clock Jitter: is defined as the root-mean-square (RMS) average of the most recent offset
differences, and it represents the nominal error in estimating the offset (of the clock).
• Clock wander: is the RMS of exponentially weighted frequency differences. This is not used
directly, but can, along with the jitter, be a highly useful monitoring and debugging tool.
•
Stratum: the level of each server in the hierarchy is defined by a stratum number. Primary
servers are assigned stratum one.