Ntp Overview - 3Com Switch 4800G 24-Port Configuration Manual

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NTP Overview

Applications of NTP
NTP C
n
The local clock of a Switch 4800Gcannot be set as a reference clock. It can serve
as a reference clock source to synchronize the clock of other devices only after it is
synchronized.
When configuring NTP, go to these sections for information you are interested in:
"NTP Overview" on page 947
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"NTP Configuration Task list" on page 953
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"Configuring the Operation Modes of NTP" on page 953
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"Configuring Optional Parameters of NTP" on page 956
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"Configuring Access-Control Rights" on page 957
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"Configuring NTP Authentication" on page 958
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"Displaying and Maintaining NTP" on page 960
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"NTP Configuration Examples" on page 960
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Defined in RFC 1305, the Network Time Protocol (NTP) synchronizes timekeeping
among distributed time servers and clients. NTP runs over the User Datagram
Protocol (UDP), using UDP port 123.
The purpose of using NTP is to keep consistent timekeeping among all
clock-dependent devices within the network so that the devices can provide
diverse applications based on the consistent time.
For a local system running NTP, its time can be synchronized by other reference
sources and can be used as a reference source to synchronize other clocks.
An administrator can by no means keep synchronized time among all the devices
within a network by changing the system clock on each station, because this is a
huge amount of workload and cannot guarantee the clock precision. NTP,
however, allows quick clock synchronization within the entire network while it
ensures a high clock precision.
NTP is used when all devices within the network must be consistent in
timekeeping, for example:
In analysis of the log information and debugging information collected from
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different devices in network management, time must be used as reference
basis.
All devices must use the same reference clock in a charging system.
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ONFIGURATION