System clock options, Table a-8 – Paradyne U8777 User Manual
Page 114

A. Configuration Options
A-18
May 2002
8700-A2-GB20-40
Table A-8.
System Clock Options
Primary System Clock Reference
Possible Settings (LTU, Model 8777): DSX-1 Port 1, DSX-1 Port 2, DSX-1 Port 3,
DSX-1 Port 4, DSX-1 Port 5, DSX-1 Port 6, DSX-1 Port 7, DSX-1 Port 8, Internal
Default Setting: Internal
Possible Settings (LTU, Model 8779): G.703 Port 1, G.703 Port 2, G.703 Port 3,
G.703 Port 4, G.703 Port 5, G.703 Port 6, G.703 Port 7, G.703 Port 8, Internal
Default Setting: Internal
Possible Settings (NTU): DSL Port 1, DSL Port 2, DSL Port 3, DSL Port 4, DSL Port 5,
DSL Port 6, DSL Port 7, DSL Port 8
Default Setting: DSL Port 1
Determines the source of system timing. Select the most accurate clock available.
DSX-1 Port
n
(Model 8777) – Timing is derived from the specified port. To be a valid clock
source, the port must be enabled and must derive its timing from the DSX-1 network.
NOTE: If the DSX-1 port is configured for Bypass mode, the Primary Clock Source
configuration option on the DSX-1 Interface Options screen must be set to DSX-1, not
Internal (see
). All ports configured as system clock sources must be
traceable to the same clock reference.
G.703 Port
n
(Model 8779) – Timing is derived from the specified port. To be a valid clock
source, the port must be enabled and must derive its timing from the G.703 network.
NOTE: If the G.703 port is configured for Bypass mode, the Primary Clock Source
configuration option on the G.703 Interface Options screen must be set to G.703, not
Internal (see
). All ports configured as system clock sources must be
traceable to the same clock reference.
DSL Port
n
– Timing is derived from the specified port. The port must be enabled and in a
cross-connection.
Internal – Timing is derived from the internal oscillator, which provides a Stratum 4
reference.
Secondary System Clock Reference
Possible Settings (LTU, Model 8777): DSX-1 Port 1, DSX-1 Port 2, DSX-1 Port 3,
DSX-1 Port 4, DSX-1 Port 5, DSX-1 Port 6, DSX-1 Port 7, DSX-1 Port 8, Internal
Default Setting: Internal
Possible Settings (LTU, Model 8779): G.703 Port 1, G.703 Port 2, G.703 Port 3,
G.703 Port 4, G.703 Port 5, G.703 Port 6, G.703 Port 7, G.703 Port 8, Internal
Default Setting: Internal
Possible Settings (NTU): DSL Port 1, DSL Port 2, DSL Port 3, DSL Port 4, DSL Port 5,
DSL Port 6, DSL Port 7, DSL Port 8
Default Setting: DSL Port 1
Determines the source of system timing if the primary system clock source fails. If the
secondary clock source fails, the unit switches to the internal clock.
DSX-1 or G.703 Port
n
– Timing is derived from the specified port. To be a valid clock
source, the port must be enabled and must derive its timing from the DSX-1 or G.703
network.
DSL Port
n
– Timing is derived from the specified port. The port must be enabled.
Internal – Timing is derived from the internal oscillator, which provides a Stratum 4
reference.