Huawei NetEngine5000E Configuration Manual page 25

HUAWEI NetEngine5000E Core Router
Configuration Guide - System Management
Working Mode
Peer Mode
Broadcast Mode
Issue 01 (2011-10-15)
Location and
Synchronization Direction
In this mode, you need to
configure NTP only on the
symmetric active end. The
symmetric active end and
symmetric passive end can be
synchronized with each other.
Note that the clock with a higher
stratum is synchronized to the
one with a lower stratum.
In this mode, you need to
configure both, the server and
the client.
The client can be synchronized
with the server but the server
cannot be synchronized with the
client.
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2 NTP Configuration
Working Principle
1. The symmetric active
end sends a
synchronization request
packet to the symmetric
passive end with the
mode field being set to 1.
(The value 1 indicates
the symmetric active
mode.)
2. Upon receiving the
request packet, the
symmetric passive end
automatically works in
symmetric passive mode
and sends a response
packet with the mode
field being set to 2. (The
value 2 indicates the
symmetric passive
mode.) Symmetric
passive also forms a
dynamic session with
symmetric active.
1. The server periodically
sends clock
synchronization packets
to the broadcast address
255.255.255.255.
2. The client senses
broadcast packets from
the server.
3. After receiving the first
broadcast packet, to
estimate the network
delay, the client enables
a temporary server/client
model for exchanging
messages with the
remote server.
4. The client then works in
broadcast client mode,
and continues to sense
the incoming broadcast
packets to synchronize
the local clock.
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