Comtech EF Data CDM-425, Installation And Operation Manual

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CDM-425 Advanced Satellite Modem
Revision 0
Appendix I I–18 MN-CDM-425
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As shown in Figure I-14:
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The first segment is between the RNC/BSC and the CDM-425 Advanced Satellite Modem
‘A’ (near-end modem) LAN port. In this segment, the RNC/BSC is the master , and the
near-end modem LAN port is the slave .
Using the ‘A’ front panel or its Web Server Interface, set the PTP Grandmaster on this
near-end modem as LAN .
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The second segment is from the CDM-425 Advanced Satellite Modem ‘A’ (near-end
modem) WAN port to the CDM-425 Advanced Satellite Modem ‘B’ (distant-end modem)
WAN port, in which the near-end modem WAN port is the master and the distant-end
modem WAN port is the slave .
Using the ‘B’ front panel or its Web Server Interface, set the PTP Grandmaster on this
distant-end modem as WAN .
•
Accordingly, the third segment between the CDM-425 Advanced Satellite Modem ‘B’
(distant-end modem) LAN port and the BTS defines the distant-end modem’s LAN port as
the
master and the BTS as the slave .
As configured here, each modem has established independent Wireless Receiver/Transmitter
(WRT) protocol segments – one for LAN and other one for WAN. This defines the boundary clock
time distribution configuration, where the slave to one interface provides a master clock to the
other interfaces.
Symbol Designation Function
Master The Master device maintains the clocks.
Slave The Slave device synchronizes its clock to the Master device’s clock.
Figure I-14. PTP Master/Slave Assignment Example
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