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CHAPTER 4: Applications
Weekend and Time of Day Lockout
The CSU/DSU MS DBU may be configured not to enter dial-backup mode
at certain times of day or on weekends. This protects the customer from being
charged for a switched call during off hours should the dedicated circuit fail.
See Chapter 9 for more information.
C
ONDITIONS FOR
R
ETURNING TO THE
DDS C
IRCUIT
The CSU/DSU MS DBU can be configured to automatically revert to the DDS
circuit from the dial-backup mode or wait to be returned to the DDS manually.
Once the CSU/DSU MS DBU enters dial-backup mode, the unit polls the DDS
circuit once every 100 ms to determine if the condition causing the DDS circuit
failure has been corrected. Once the CSU/DSU MS DBU determines that the
problem has been properly corrected and the DDS circuit is stable, it will wait
for the amount of time specified in the restore timer (1 to 255 minutes) before
reverting to the DDS circuit. Polling of the DDS circuit is non-intrusive and
return to the DDS circuit generally takes 2 to 3 seconds. The backup
connection is maintained for one minute after the DDS circuit is restored.
See Chapter 9 for more detailed information.