Introduction Of Clock Synchronization Configuration; Overview Of Clock Synchronization Configuration; Clock Synchronization Supported By The Ne80E/40E; Setting Basic Configurations For Clock Synchronization - Huawei netengine80e Configuration Manual

HUAWEI NetEngine80E/40E Router
Configuration Guide - Basic Configurations

9.1 Introduction of Clock Synchronization Configuration

Clock synchronization ensures that digital pulse signals are sent and received in a specific
timeslot.

9.1.1 Overview of Clock Synchronization Configuration

Clock synchronization ensures that digital pulse signals are sent and received in a specific
timeslot.
Definition
Synchronization must be maintained on Data Communications Networks (DCN). The sending
end places a pulse in a specified timeslot at the end of the digital pulse signal. The receiving end
extracts the pulse in the specified timeslot, so that normal communications between sending and
receiving ends are guaranteed. A clock ensures that signals are sent in a certain timeslot and then
received and extracted from that timeslot.
Purpose
Clock synchronization is used to keep differences in clock frequency and phase among network
elements on a digital network within a specific range. If the differences exceed the specified
range, bit errors and jitter occur and transmission performance is degraded.

9.1.2 Clock Synchronization Supported by the NE80E/40E

Clock Transmission
The clock signals can be transmitted on the Ethernet network, Asynchronous Transfer Mode
(ATM) network, and Synchronous Digital Hierarchy (SDH) network.
Tracing BITS Clock
For the Building Integrated Timing Supply System (BITS) clock source, the clock module
extracts Synchronization Status Messages (SSMs) from the 2.048 Mbit/s stream signals, or the
Main Processing Unit (MPU) sets a preset SSM level for the 2.048 MHz clock signals.
Stratum-3 Clock Source
The device that provides the clock signals for the local device is called the clock source. The
local device may have multiple clock sources. Include BITS0, BITS1, BITS2 and PTP.

9.2 Setting Basic Configurations for Clock Synchronization

This section describes how to set basic configurations for clock synchronization.
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