Televes OLT 769401, Руководство пользователя

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Descripción del producto
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Transparent clock
A transparent clock is a device or a switch that calculates the time it requires to forward traffic and updates the PTP time
correction field to account for the delay, making the device transparent in terms of time calculations.
2.12.4.1 Client/Server model
Master clock, slave clock (ordinary clock)
Intermediary nodes may or may not support IEEE1588 PTP (unlike SyncE)
On-path support mechanisms:
Boundary clock
t acts as a slave clock at port that connects to the grandmaster, and as a master to all other ports
t isolates the “downstream” clocks from any delays and jitter within the switch/routers
Transparent clock
It measures residence time of PTP events
2.12.5 SYNC-E and IEEE 1588v2/PTP at the OLT equipment
Network clocking is supported on the following ports:
1GbE,
10GbE.
2.12.5.1 Clock configurations supported by the OLT
:
Different configurations are supported:
Clock Recovery : System clock is recovered from the clocking source (GbE, 10Gbe and 100Gbe).
Clock Recovery from External Interface : System clock is recovered from clocking source or a GPS interface.
Line to External : The clock received from an interface is forwarded to an external Synchronization Supply Unit (SSU).
The following sync. parameters are configurable in the OLT
Quality level Mode – Active or inactive
Reversibility level Mode– Active or inactive
Reversibility time – 0 to 3600 s
Holdover Message delay switching Message delay – 500 to 2000 ms
Switching Message delay – 180 to 500 s
Minimum Quality Before Squelch – Inactive, PRC G.811, SSU-A, SSU-B,SEC or DNU
Send value after Quality Unknown - PRC G.811, SSU-A, SSU-B,SEC or DNU
Number of external sync.- 2 IN and 2 OUT