Networking Guide
Chapter 16, Configuring the Network Time Protocol (NTP)
An example synchronization subnet
An example synchronization subnet
Assume that hosts acapulco, seattle, and moscow
are stratum 2 servers in the mynet.com network. Assume
also the following:
-
acapulco polls two stratum 1 servers,
clock.llnl.gov and
clepsydra.dec.com.
-
seattle polls two stratum 1 servers,
ntp.olivetti.com and
ntp1.ossi.com.
-
moscow polls two stratum 1 servers,
apple.com and norad.arc.nasa.gov.
-
acapulco polls seattle and moscow.
-
seattle polls acapulco and moscow.
-
moscow polls acapulco and seattle.
-
chicago and the rest of the machines at mynet.com are
at stratum 3 and listen for broadcast NTP packets from
the three stratum 2 hosts.

A → B means A polls B or A listens for broadcast NTP packets
from B.
C ←→ D means C polls D and vice versa.