ZyXEL Communications Prestige 128 Plus User Manual page 190

Prestige 128+ ISDN Router
#call
Max
Min
Total
15-22
This is the number of calls made to or received from that telephone
number.
This is the length of time of the longest telephone call.
This is the length of time of the shortest telephone call.
This is the total length of time of all the telephone calls to/from that
telephone number.
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