Nokia 7705 SAR - 3.2.6 Node Synchronization From GNSS Receiver Ports

Interface Configuration Guide 7705 SAR Interfaces
Edition: 01 3HE 11011 AAAC TQZZA 81
• 4-port DS3/E3 Adapter card (DS1/E1 channels on DS3 ports; E3 ports cannot
be channelized); differential timing on DS1/E1 channels is supported only on the
first three ports of the card
• 7705 SAR-M (variants with T1/E1 ports)
• 7705 SAR-X
• 7705 SAR-A (variant with T1/E1 ports)
• T1/E1 ports on the 4-port T1/E1 and RS-232 Combination module
A T1/E1 port can be configured to be a timing source for the node.
3.2.6 Node Synchronization From GNSS Receiver Ports
The GNSS receiver port on the 7705 SAR-Ax, 7705 SAR-Wx, and 7705 SAR-H GPS
Receiver module, and the GNSS Receiver card installed in a 7705 SAR-8 or
7705 SAR-18, can provide a synchronization clock to the SSU in the router with the
corresponding QL for SSM. This frequency can then be distributed to the rest of the
router from the SSU as configured with the ref-order and ql-selection commands;
refer to the 7705 SAR Basic System Configuration Guide for information. The GNSS
reference is qualified only if the GNSS receiver port is operational, has sufficient
satellites locked, and has a frequency successfully recovered. A PTP
master/boundary clock can also use this frequency reference with PTP peers.
In the event of GNSS signal loss or jamming resulting in the unavailability of timing
information, the GNSS receiver automatically prevents output of clock or
synchronization data to the system, and the system can revert to alternate timing
sources.
A 7705 SAR using GNSS or IEEE 1588v2 PTP for time of day/phase recovery can
perform high-accuracy OAM timestamping and measurements. Refer to the
7705 SAR Basic System Configuration Guide for information about node timing
sources.
Note: Adaptive timing and differential timing are not supported on DS1 or E1 channels that
have CAS signaling enabled.