Paradyne 316x manual Timing, 32. Common Clocking Configurations

Operation

Timing

The 316x DSU/CSU provides the ability to select a master clock (timing) source that is used to synchronize all of the T1 and data port interfaces on the DSU/CSU. When a master clock source is selected, the DSU/CSU will synchronize to the master clock and derive clocking for all of the interfaces on the DSU/CSU. The clock for each interface will be at the appropriate rate for that interface (e.g., 1.544 Mbps for the T1 interfaces, the configured port rate for the data ports) and independent of the master clock rate. This means that the master clock rate and the DSU/CSU interface rates may be different. The DSU/CSU will automatically fall back to the internal master clock when a failure of the selected master clock is detected.

NOTE

For Model 3161 DSU/CSUs, the external clock provides timing for up to eight slots in the carrier.

Each Auxiliary Backplane must have its own external clock input.

The DSU/CSU clock source configuration option enables you to select one of five sources for the master clock, either the Network T1 interface, the DSX-1 Drop/Insert T1 interface, Port 1, internal clock, or external clock. If external clocking is selected, you must use the clock rate configuration option to specify the clock rate. Two examples for configuring timing are given below. For more information on the configuration options, refer to Appendix C. Figure 3-32 shows some common clocking configurations.

3160/3164	3160/3164
	NETWORK
CLOCK: NETWORK	CLOCK: NETWORK
3160/3164	3160/3164

CLOCK: INTERNAL			CLOCK: NETWORK
		3160/3164
	3160/3164

CLOCK: EXTERNAL	CLOCK: NETWORK
3160/3164	3160/3164
PBX
CLOCK: DTE (DSX-1 CONNECTOR)	CLOCK: NETWORK
3160/3164	3160/3164
TERMINAL
EQUIPMENT
CLOCK: PORT 1	CLOCK: NETWORK
	496-14341a-01

Figure 3-32. Common Clocking Configurations

3160-A2-GB22-10 December 1996 3-49