Televes OLT 769401, User Manual

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Descripción del producto
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2.11.1.4.2 ERP TIMERS
WTR timer
May be configured by the operator in 1 minute steps between 1 and 12 minutes, the default value being 5 minutes.
WTB timer
Is defined to be 5 seconds longer than the guard timer.
Guard Timer
The period of the guard timer may be configured by the operator in 10 ms steps between 10 ms and 2 seconds, with a default
value of 500 ms.
Hold off timer
The suggested range of the hold off timer is 0 to 10 seconds in steps of 100 ms with an accuracy of ±5 ms. the default value
for hold off timer is 0 seconds.
2.12 Synchronization
The OLT equipment implements SyncE and IEEE 1588v2/PTP synchronization schemes. Timing over Packet (ToP) enables transfer of timing over an
asynchronous network. The SyncE feature requires that each network element along the synchronization path need to support SyncE.
2.12.1 Hybrid Synchronization with the OLT Equipment Family
Within the OLT equipment, SyncE may co-exist with 1588 (PTP) in a hybrid configuration mode. The hybrid mode uses the clock derived from 1588
(PTP) to drive the system clock.
2.12.2 Ethernet Synchronization Messaging Channel (ESMC)
In order to maintain a logical communication channel in synchronous network connections, Ethernet relies on a channel called Ethernet
Synchronization Messaging Channel (ESMC) based on IEEE 802.3 Organization Specific Slow Protocol standards. ESMC relays the SSM code that
represents the quality level of the Ethernet Equipment Clock (EEC) in a physical layer.
To enable communications between various nodes, the OLT equipment (SyncE mode) provides an Ethernet Synchronization Status Messaging
(ESMC, G.8264) channel, similar to SDH Synchronization Status Messaging (SSM) bytes that allow nodes to deliver their Synchronization Status to
downstream nodes. The downstream nodes use this information to select between various references or possibly switch to their internal clock in
case of failure on reference clocks.
2.12.3 Synchronous Ethernet (SyncE)
SyncE is defined by the ITU-T standards G.8261, G.8262, G.8264, and G.781. Frequency distribution protocol based Ethernet physical layer of
Ethernet. The purpose of SyncE is to distribute frequency information through an Ethernet device. In this context “frequency” and “bit-rate”
effectively have the same meaning, since SyncE attempts to determine frequency information from incoming bit streams. The basic operation of
SyncE interfaces is deriving the frequency from the received bit stream and passing that information up to the system clock,