Configuration Process of Physical Clock (NG WDM NEs)

This topic describes the process of clock configuration based on a flowchart.

The details of the clock configuration flow vary with the situation. See Figure 1, Figure 2, and Figure 3.

Figure 1 Configuration flow when the SSM protocol is disabled

Figure 2 Configuration flow when the standard SSM protocol is enabled

Figure 3 Configuration flow when the extended SSM protocol is enabled

NOTE:

The horizontal direction of the figure shows the three stages when you use the Web LCT to configure clocks.
The vertical direction of the figure shows the relationships between operation tasks at each stage.

Table 1 provides the details about the processes for configuring physical clocks.

**Table 1** Clock configuration processes
Operation		Remarks
Configuring the Frequency Source Mode		Mandatory. Before configuring clocks, Frequency Source Mode must be specified as required. If physical clock frequency synchronization is used, select Physical Synchronization; if IEEE 1588v2-compliant frequency synchronization is used, select PTP Synchronization .
Configuring Attributes of Transport Clock for Boards	Setting Synchronous Clock Enabled	Optional. When line boards such as TN52ND2 and TN52TOG are used to provide clock synchronization, Synchronous Clock Enabled must be set.
Configuring Attributes of Transport Clock for Boards	Setting Synchronous/Asynchronous Mode	Optional. when TN52TOG boards are used to provide time synchronization, Synchronous/Asynchronous Mode must be set.
Configuring External Clock Ports	Setting Port Cascading for external ports on clock boards	Optional. This operation is performed only when an NE needs to receive or transmit external clock signals. NOTE: Applicable to OptiX OSN 8800 series.
Configuring External Clock Ports	Configuring Phase-Locked Source Output of External Clocks	Optional. This operation is performed only when an NE needs to receive or transmit external clock signals.
Configuring Clock Attributes	Configuring System Clock Source Priority Table	Mandatory. This operation specifies the priority of each required clock source. This provides a criterion for selecting clock sources in case of a clock switching event.
	Configuring Clock Quality	Mandatory. In general, the default value Automatic Extraction is recommended.
	Setting Higher-Priority Clock Source Reversion	Mandatory. When an NE has multiple clock sources and the currently traced clock source degrades, the NE will trace another clock source with higher quality. After the degraded clock source is restored, the NE can automatically trace the degraded clock source only when Higher-Priority Clock Source Reversion is set to Auto-Revertive.
	Setting Clock Source WTR Time (min)	Mandatory. When the clock source traced by an NE becomes faulty, the NE changes to trace another clock source after the specified Clock Source WTR Time (min) elapses. The recommended setting for WTR time is five minutes.
Configuring the Clock Source Protection	Configuring SSM Protection	Optional. This operation is required only when the standard or extended SSM protocol is enabled.
	Setting Clock Subnet	Optional. This operation is required only when the extended SSM protocol is enabled.
	Configuring SSM Output	Optional. This operation is required only when the standard or extended SSM protocol is enabled.
Configuring Clock Source Switching	Configuring Switching Conditions for Clock Sources	Optional. Users can customize the conditions for clock switching when an NE traces a line clock. This ensures that the NE will begin tracing another clock in a timelier manner after the previously tracked clock source fails, thereby minimizing the impact on services.
	Setting Clock Source Switching	Optional. By setting Clock Source Switching, users can enable a configured clock source to participate in clock switching, or disable it from participating in clock source switching. This operation is actually to lock or unlock the clock source.
	Performing clock source switching	Optional. When the clock source of an NE on the network degrades, the downstream NEs may not be able to perform clock switching. To prevent services on the downstream NEs from being affected, users need to manually perform clock switching on the downstream NEs by setting Clock Source Switching to Enabled.
Viewing Clock Synchronization Status		Mandatory. After all the clock configuration processes are completed, users need to query all ports for the clock synchronization status to ensure that the port synchronization status is the same as defined in the networking diagram.