[RI Swamp Yankee]

The DSL modem is intended to remain on all the time. When shut off and back on it usually takes about 5 minutes to "retrain". The retraining process is where the DSL modem and the Central Office DSLAM (Digital Subscriber Line Access Multiplexer) send analog tones back and forth to decide which analog tones to use to create the simulated digital signal. (Yes, DSL is really all analog!) Often, if the DSL modem is turned off for a long period the DSLAM will lock out the line when it detects there is nothing at the far end (the subscriber end) rather that keep up the attempts at retraining.