ZyXEL Communications Prestige 28641 - Manual (Page 72)

58 Remote Node Configuration
Utility number for longer than the specified Add Persist value. Similarly,
the second channel will be dropped if the traffic level falls below the low
Target Utility number for longer than the Subtract Persist value.
The Target Utility specifies the line utilization range at which you want
the Prestige to add or subtract bandwidth. The range is 30 to 64 kbps
(kilobits per second). The parameters are separated by a -. For
example, 30-60 means the add threshold is 60 kbps and subtract
threshold is 30 kbps. The Prestige will perform bandwidth on demand
only if it initiates the call. Addition and subtraction are based on the
value set in the BOD Calculation field. If this field is set to Transmit or
Receive, then traffic in either direction will be calculated to determine if
a link should be added or dropped. Transmit will only use outgoing
traffic to make this determination, and Receive will only use incoming
traffic to make this determination.
If, after making the call to bring up a second channel, the second
channel does not succeed in joining the Multilink Protocol bundle
(because the remote device does not recognize the second call as
coming from the same device), the Prestige will hang up the second
channel and continue with the first channel alone.