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The 'Extension Length' used to determine how many of the DID digits (starting from the end) are to be used as the Extension no.
Timeout
Controls how long the call should ring the no. before dropping giving up (as the call was not answered) and progressing to the next route step.
You can use the Timeout to fail over to try a second phone, play a message, send the call to a voicemail box etc.
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A good example of the use of this option is creating a Dial Step followed by a Voicemail Step. You want the call to go to voice mail VoiceMail only when the call isn't answered.
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