Setting Up SyncE

If your equipment has this optional hardware feature, you can use the synchronous Ethernet (SyncE) feature to synchronize the unit and all its outputs over Ethernet networks. SyncE takes the clock signal from the selected clock reference port and transmits it to all other ports. You also have the option to define a Secondary Clock Source on another physical port.

To set up SyncE

Access the page Port ▶SyncE.
Select Enable SyncE.
Complete the required fields, then click Apply.
For more information on specific parameters, refer to the following table.

SyncE/ESMC Parameters (Port ▶SyncE)

Parameter	Description
Enable SyncE	Enables or disables the synchronous Ethernet feature. When disabled, all ports on the system operate as clock master. When enabled, the clock reference port(s) operate as clock slave (s) and all the other ports on the system operate as masters, transmitting clock signal from clock reference port. When enabled, clock status information is also displayed.

Options

Parameter	Description
Primary Clock Source	The port from which the Primary Reference Clock is recovered.
Secondary Clock Source	The port from which the Secondary Reference Clock is recovered. This parameter is optional and may be set to none if only a single reference clock is preferred.
Revertive	Enables or disables the revertive clock selection feature. When enabled, the clock selector is allowed to switch back to a higher-priority clock source that previously failed when it becomes available again When disabled, the clock selector is allowed to revert to a lower priority clock source, but only if the currently selected source becomes unavailable. In this mode, the selector cannot revert to a clock that previously failed.
Wait-to-Restore Delay (sec)	The system will wait for this many seconds before reverting to a clock available after a failure. Note: This feature applies when ESMC QL Mode is enabled.
Manual Clock Source	This sets the clock selector to use a specific clock source, regardless of priority. Note: The system will not switch to an invalid clock and it will not switch to a clock of inferior quality (if ESMC QL mode is enabled). If none is specified, the clock source is selected automatically.
ESMC QL Mode	Enable or disable the ESMC QL mode. ESMC QL messages containing clock quality information can be sent and received only if this is enabled. If enabled, clock quality information can then be used to automatically select the best clock reference available.
ESMC Forward extended TLV	ESMC messages may contain type-length-values (TLV) other than the mandatory QL TLV. These are referred to as extended TLVs. Their content is not used in the system. When enabled, extended TLVs will be forwarded from incoming SyncE ports to all outgoing SyncE ports; if not enabled, they are stripped out. Note: This feature applies when ESMC QL Mode is enabled.

Status

Parameter	Description
Clock Selector	The clock source that is currently in use by the SyncE hardware. Possible values are: Primary: The primary reference clock is in use. Secondary: The secondary reference clock is in use. Local: The local oscillator is in use. This should only happen when SyncE is disabled.
Primary Clock Status	The current status of the primary reference clock.
Secondary Clock Status	The current status of the secondary reference clock.
Clock Selection Change Count	The number of times the clock reference was changed.
Current QL State	The current QL status. Note: This feature is not available if ESMC QL Mode is disabled.
Previous QL State	The previous QL status with the time elapsed in seconds (with millisecond resolution) since the change occurred. Note: This feature is not available if ESMC QL Mode is disabled.
Previous Clock Selector	The previous clock selector with the time elapsed in seconds (with millisecond resolution) since the change occurred.

Port Statistics Summary (only available if ESMC QL mode is enabled)

Parameter	Description
Status	The following colors indicate SyncE port status: Green: The port is up and running. Blue: The port is enabled and a signal is detected. Red: The port is enabled but the physical link is down and no signal is detected. Yellow: The port is not totally functional. Gray: The port is disabled.
Port Name	The name that identifies the port. A link can be clicked to access detailed SyncE/ESMC port statistics.
Tx QL	Last transmitted clock QL on the port.
Rx QL	Last received clock QL on the port.
QL State	Current QL receive status used for selection process if the port is a reference clock. Note: The QL-FAILED state indicates that the port is in a failed condition.
State Duration	Time elapsed in seconds since QL state was last changed.

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