Operation Manual – NTP
H3C S3610&S5510 Series Ethernet Switches
Chapter 1 NTP Configuration
1-5
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 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 the service host for
the client.
z
Authenticator: authentication information.
1.1.4 Operation Modes of NTP
Devices running NTP can implement clock synchronization in one of the following
modes:
I. Server/client mode
Figure 1-3
Server/client mode
When working in the server/client mode, a client sends a clock synchronization
message to servers, with the Mode field in the message set to 3 (client mode). Upon
receiving the message, the servers automatically work in the server mode and send a
reply, with the Mode field in the messages set to 4 (server mode). Upon receiving the
