Patent ID: 7286485

Claim:
A method for controlling a data flow in a data network at an element having a queue, the method comprising: specifying a plurality of precedence grades, each of said precedence grades having a priority associated thereto; for each precedence grade, calculating a cumulative queue size q(n) where q(n) is the sum of the queue size for a particular precedence grade under consideration plus the queue sizes of all precedence grades with a higher priority than said particular precedence grade under consideration; for each precedence grade calculating an error signal e(n), according to the relation e ( n )=( q ( n )− T ), where T is an-assigned precedence grade queue capacity at time n; for each precedence grade computing a mark/drop probability p(n) according to the relation p ( n )=min{max [ p ( n− 1)+α· e ( n )/2 ·T, 0], θ} where α is a control gain, and 0<θ≦1; and for each precedence grade executing a packet mark/drop routine based upon the calculated mark/drop probability p(n).