System and method employing last occurrence and sliding window technique for determining a minimum and maximum value

Abstract

A system and method for determining the minimum and/or maximum values from a number of sample parameter values utilizes a table of last occurrence (TOLO-table), together with a sliding window or filter, to greatly enhance the speed and efficiency when determining the minimum and/or maximum value from a number of sample parameter values that fall within the sliding window. The TOLO-table typically includes a parameter column for storing entries for each one of a limited number of discrete parameter values, and also includes a time stamp column which provides entries for storing time of receipt data associated with each parameter value defined in the parameter column. Alternatively, an order number column may be employed for storing number order entries corresponding to the order in which the parameter values are received. Every time a parameter value is received, the time stamp or order number entry associated with the parameter value is updated to the current time or order number. The sliding window may be defined on the basis of time or by a selected number of sample parameter values. The parameter values falling within the sliding window are scanned to determine the minimum and/or maximum of the applicable parameter values. A minimum/maximum determination methodology that employs a TOLO-table and sliding window may be used in a wide variety of applications, and is particularly useful in ATM network applications, particularly in implementing the cell discarding strategy of a network node.