Black Box 5000 series Reference Manual page 58

Menus Reference Manual: Frame Relay Set-Up Menu
6 - Monitored Events
The Monitored Events option specifies the number of status inquiries that are to be monitored when determining the
Error Threshold. By default, if the P1700 does not receive responses to 3 of the last 4 status inquiries, the link will be
considered failed.
Default: [4]
Range: 1 to 10
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