This is the per-port equivalent of the switch-wide high-water mark: the largest number of stations ever seen active on this specific port at one time since the last switch reset, including that port's own default MAC address entries. An admin compares this to cat2600TsPortMaxStations to see if a particular port's segment has ever approached its per-port address-table capacity, which is more granular than the aggregate switch-wide figure. A port showing a peak of 200 stations on a segment with a 256-station cap would flag that link as worth monitoring closely.