3Com 4500 Configuration Manual page 542

Server/client mode
Figure 1-2 Server/client mode
Symmetric peer mode
Figure 1-3 Symmetric peer mode
Active peer
In peer mode, both sides
can be synchronized to
each other
In the symmetric peer mode, the local S4500 Ethernet switch serves as the symmetric-active peer and
sends clock synchronization request first, while the remote server serves as the symmetric-passive
peer automatically.
If both of the peers have reference clocks, the one with a smaller stratum number is adopted.
Broadcast mode
Figure 1-4 Broadcast mode
Passive peer
Network
Clock synchronization
Works in passive peer
request packet
mode automatically
Response packet
Synchronize
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