Chapter 7 Ntp Configuration; Brief Introduction To Ntp; Ntp Functions; Basic Operating Principle Of Ntp - Huawei Quidway S6500 Series Operation Manual

Operation Manual - System Management
Quidway S6500 Series Ethernet Switches

Chapter 7 NTP Configuration

7.1 Brief Introduction to NTP

7.1.1 NTP Functions

As the network topology gets more and more complex, it becomes important to
synchronize the clocks of the equipment on the whole network. NTP (Network Time
Protocol) is an application layer protocol of TCP/IP protocol suite and used for
advertising the accurate time throughout the network.
NTP ensures the consistency of the following applications:
For the incremental backup between the backup server and client, NTP ensures
the clock synchronization between the two systems.
For multiple systems that coordinate to process a complex event, NTP ensures
them to reference the same clock and guarantee the right order of the event.
Guarantee the normal operation of the inter-system (Remote Procedure Call).
Record for an application when a user logs in to a system, a file is modified, or
some other operation is performed.

7.1.2 Basic Operating Principle of NTP

The following figure illustrates the basic operating principle of NTP:
1. 1. 1. 1.
2. 2. 2. 2.
3. 3. 3. 3.
4. 4. 4. 4.
Figure 7-1 Basic operating principle of NTP
NTP Packet NTP Packet NTP Packet NTP Packet 10:00:00 am 10:00:00 am
10:00:00am 10:00:00am
Network Network Network Network
LS_A LS_A LS_A LS_A
Network Network Network Network
LS_A LS_A LS_A LS_A
NTP Packet NTP Packet NTP Packet NTP Packet 10:00:00am 10:00:00 am 10:00:00am 10:00:00 am
Network Network Network Network
LS_A LS_A LS_A LS_A
NTP Packet received at 10:00:03 NTP Packet received at 10:00:03 am NTP Packet received at 10:00:03 am NTP Packet received at 10:00:03
Network Network Network Network
LS_A LS_A LS_A LS_A
Huawei Technologies Proprietary
LS_B LS_B LS_B LS_B
NTP Packet NTP Packet NTP Packet NTP Packet 10:00:00 am 10:00:00am 10:00:00 am 10:00:00am 11:00:01 am 11:00:01am 11:00:01 am 11:00:01am
LS_B LS_B LS_B LS_B
11:00:01am 11:00:01 am 11:00:01am 11:00:01 am 11:00:02 am 11:00:02 am 11:00:02am 11:00:02am
LS_B LS_B LS_B LS_B
LS_B LS_B LS_B LS_B
7-1
Chapter 7 NTP Configuration