WESM zl Management and Configuration Guide WT.01.28 and greater

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Configuring the ProCurve Wireless Edge Services zl Module
Enabling Secure Network Time Protocol (NTP)
■ Root Dispersion—a 32-bit unsigned fixed-point number indicating the nominal
error relative to the primary reference source, in seconds with fraction point
between bits 15 and 16. The values that normally are displayed in this field range
from 0 to several hundred milliseconds.
■ Reach—displays the peer reachability (bit string, in octal).
■ Delay—the number of milliseconds required for NTP packets to make the round-
trip from the module to the remote server and back. The delay is an important
factor when the module selects the “best” server. Minimizing delay is one reason
why you want to pick servers that are close to you.
■ Offset—the difference in milliseconds between the clocks in your host and the
remote resource. As clocks synchronize, the offset decreases. Your mode and
the mode of the peer, as well as other factors, dictate whether the module
synchronizes to the remote resource.
■ Dispersion—A measure, in seconds, of how scattered the time offsets have been
from a given time server.
■ Precision—an eight-bit signed integer indicating the precision of the local clock,
in seconds to the nearest power of two. The values that normally are displayed
in this field range from -6 for mains-frequency clocks to -20 for microsecond
clocks found in some workstations.
■ Filter Delay—displays, in milliseconds, the last eight delay values (round-trip
delay between the master NTP server and the Module).
■ Filter Offset—displays, in milliseconds, the last eight offset values (difference
between the Module time and the master NTP server time).
■ Filter Error—displays the last eight approximate error values of that sample.
To refresh the screen, click the Refresh button.
To close the screen, click the Close button.
Viewing Secure NTP Status
The Special Features > Secure NTP > Secure NTP Status screen displays current
status information for the Wireless Edge Services zl Module’s NTP services. (The
NTP Associations tab shows the status for all associations with potential time
sources.)