Ntp Configuration; Ntp Overview; Applications Of Ntp - H3C S5820X Series Configuration Manual

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NTP Configuration

This chapter includes these sections:

NTP Overview

NTP Configuration Task List
Configuring the Operation Modes of NTP
Configuring Optional Parameters of NTP
Configuring Access-Control Rights
Configuring NTP Authentication
Displaying and Maintaining NTP
NTP Configuration Examples
NTP Overview
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 that runs NTP, its time can be synchronized by other reference sources and
used as a reference source to synchronize other clocks.

Applications of NTP

An administrator is unable to keep time synchronized 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 different
devices in network management, time must be used as reference basis.
All devices must use the same reference clock in a charging system.
To implement certain functions, such as scheduled restart of all devices within the network,
all devices must be consistent in timekeeping.
When multiple systems process a complex event in cooperation, these systems must use
that same reference clock to ensure the correct execution sequence.
For incremental backup between a backup server and clients, timekeeping must be
synchronized between the backup server and all the clients.
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