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)
NTP defines two additional modes:
■ Peer mode—Peers operate on an equal level. Peers act as both clients and servers
to each other. They send each other control queries either to synchronize their
clocks entirely or simply to exchange information.
■ Broadcast mode—Broadcast mode is similar to client-server mode. Rather than
responding to direct time requests, however, a server broadcasts time informa-
tion.
To configure your Wireless Edge Services zl Module to act as a peer to another NTP
device, add that device as an NTP neighbor in peer mode.
If your network includes an NTP server that operates in broadcast mode, you can
enable your module to listen for these broadcasts.
NTP Hierarchy
NTP uses a hierarchical system of 16 clock stratum levels (numbered 0 through 15)
to define:
■ the distance (number of “hops”) from the reference clock to the Secure NTP
server
■ the associated accuracy
Figure 2-88 illustrates the top four NTP clock stratum levels.