Paradyne 3161-B3, 3165-A2, 3164-A2 manual Providing Backup Capability, Selecting the Timing Source

3. Operation

7.From the Clear Channel screen, select NET to clear all DS0 channels assigned to the network interface. Or, select DTE to clear all DS0 channels assigned to the DTE Drop/Insert (DSX-1) interface. Or, select a port to clear all assignments for that data port.

Clear Channel:

NET DTE Port1

F1 F2 F3

Providing Backup Capability

If the T1 network fails, the DSU/CSU provides the ability to reconfigure the unit and restore (at least partially) priority data circuits through an external backup device.

You can store backup configuration options in the Customer 2 set of customer-defined configuration options. The Enterprise MIB variable devConfigAreaCopy allows the entire contents of one configuration area to be copied into another configuration area via SNMP.

By cross-connecting two synchronous data ports to each other, one port can provide a backup path for the other. As soon as the ports are configured to be mapped to each other, Data Set Ready (DSR) for the ports is turned on. The external backup device can be configured to initiate dialing when it detects the off-to-on transition of DSR.

Selecting the Timing Source

The 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. The clock for each interface is 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 it is independent of the master clock rate. This means that the master clock rate and the DSU/CSU interface rates may be different.

The clock source configuration options enable you to select either the network interface, a synchronous data port, the internal clock, the DTE Drop/Insert (DSX-1) interface, or an external clock. If external clocking is selected, you must use the clock rate configuration option to specify the clock rate. Figure 3-12, Common Clocking Configurations, shows some common clocking configurations. Two sample procedures for configuring timing are given in the following sections, Configuring for Network Timing on page 3-47and Configuring for External Timing on page 3-47.For more information on configuration options, refer to Appendix C, Configuration Options.

3160-A2-GB21-90 February 2001 3-45