Zte ZXR10 8900E series, Product Description

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ZXR10 8900E series Core Switch Product Description
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Measurement (ETH-DM). It supports Ethernet link OAM, link discovery, link state
monitoring, remote defect indication, and remote loopback that conform to IEEE802.3ah.
3.6 Clock synchronization
Because of telecom bearing IP trend, there are clock requirements for Ethernet to provide
precision clock for mobile wireless network. Mobile network has high requirements for
high-precision synchronization. Its synchronization consists of frequency synchronization
and time synchronization. ZXR10 8900E supports Synchronous Ethernet and 1588v2
solution which uses synchronous Ethernet technology for clock frequency
synchronization, and IEEE 1588 phase fine control and time maintenance for clock time
synchronization.
ZXR10 8900E can configure different clock source priorities. Clock sources are selected
according to different priorities. The clock source with the highest priority will take effect in
the earliest time. If the clock fails, the clock source with the second highest priority will
take effect, and the rest will go similarly. The restoration policy of clock source is: If the
clock with high priority is restored, it can be configured to select whether to switch back.
3.6.1 Clock source
ZXR10 8900E support 5 clock sources, and the main control decides which clock source
information is distributed to the system.

Local clock: Local clock of system hardware, the most basic clock signal.

BITS: Support 2MHz analog signal and 2Mbits digital clock signal.

GPS: Traditional mobile network clock source providing high-precision clock signal
and 1PPS+TOD signal.

SyncE: Support Synchronous Ethernet interface, and restore and extract the clock
from physical layer.

1588v2: IEEE 1588v2 is a precision time synchronization protocol which transfers
messages between active and standby equipments to precisely synchronize
master/slave clock and time.
3.6.2 Synchronous Ethernet
Synchronous Ethernet (SyncE) technology adopts Ethernet link code stream to restore
the clock. It synchronizes frequency rather than synchronization phase, and needs all
bearer network equipments to support synchronous Ethernet features. ZXR10 8900E can
extract the clock from Ethernet link, or get support reference clock from external
synchronous interface (including BITS and GPS) as system clock. The system selects
the proper system clock source and export clock source according to synchronization