Operation modes of ntp, Client/server mode – H3C Technologies H3C WX6000 Series Access Controllers User Manual
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z
Mode: a 3-bit code indicating the work mode of NTP. This field can be set to these values: 0 –
reserved; 1 – symmetric active; 2 – symmetric passive; 3 – client; 4 – server; 5 – broadcast or
multicast; 6 – NTP control message; 7 – reserved for private use.
z
Stratum: an 8-bit integer indicating the stratum level of the local clock, with the value ranging from 1
to 16. The clock precision decreases from stratum 1 through stratum 16. A stratum 1 clock has the
highest precision, and a stratum 16 clock is not synchronized and cannot be used as a reference
clock.
z
Poll: 8-bit signed integer indicating the poll interval, namely the maximum interval between
successive messages.
z
Precision: an 8-bit signed integer indicating the precision of the local clock.
z
Root Delay: roundtrip delay to the primary reference source.
z
Root Dispersion: the maximum error of the local clock relative to the primary reference source.
z
Reference Identifier: Identifier of the particular reference source.
z
Reference Timestamp: the local time at which the local clock was last set or corrected.
z
Originate Timestamp: the local time at which the request departed from the client for the service
host.
z
Receive Timestamp: the local time at which the request arrived at the service host.
z
Transmit Timestamp: the local time at which the reply departed from the service host for the client.
z
Authenticator: authentication information.
Operation Modes of NTP
Devices running NTP can implement clock synchronization in one of the following modes:
z
Client/server mode
z
Symmetric peers mode
z
Broadcast mode
z
Multicast mode
You can select operation modes of NTP as needed. In case that the IP address of the NTP server or
peer is unknown and many devices in the network need to be synchronized, you can adopt the
broadcast or multicast mode; while in the client/server and symmetric peers modes, a device is
synchronized from the specified server or peer, and thus clock reliability is enhanced.
Client/server mode
Figure 6-3 Client/server mode