WESM zl Management and Configuration Guide WT.01.28 and greater

2-144
Configuring the ProCurve Wireless Edge Services zl Module
Enabling Secure Network Time Protocol (NTP)
4. If you checked the Act as NTP Master Clock box (in step 3), in the Clock Stratum
field, enter how many hops (from 1 to 15) the Wireless Edge Services zl Module
is from an NTP time source.
Valid values are from 1 to 15, although your clock stratum value should be at
least 2 (because you are not actually connected to a stratum0 device). Typically,
you should set the stratum somewhat higher (for example, to 10): the Wireless
Edge Services zl Module automatically chooses the NTP resource with the
lowest stratum number, and its internal clock should not take precedence over a
more robust clock.
The NTP-enabled module compares the time reported by several sources and
does not synchronize to a time source whose time is significantly different than
others, even if its stratum is lower. You do not need to worry that your module
will synchronize to a NTP server that is not synchronized itself.
5. Check the Listen to NTP Broadcasts box to allow the Wireless Edge Services zl
Module to receive the time from an NTP broadcast server.
The module and the NTP broadcast server must be on the same subnetwork.
6. If you check the Listen to NTP Broadcasts box, you have the option of setting
the broadcast delay in the Broadcast Delay field.
By default, the Wireless Edge Services zl Module exchanges a series of packets
with the broadcast server to estimate the average delay to the server. With this
information, the module knows by how much to offset the time it receives from
the server.
Alternatively, you can manually specify the estimated delay to the server by
entering a value between 1 and 999999 microseconds in the Broadcast Delay
field.
7. Click the Apply button.
You can now set up optional security mechanisms (see “Applying ACLs to NTP
Services” on page 2-145 and “Configuring Authentication for Secure NTP” on
page 2-147) and add neighbors (see “Configuring NTP Neighbors” on page
2-150.)