Switching system having means for congestion control by monitoring

Abstract

In a switching system connected between a plurality of input lines and a plurality of output lines, destinations of a plurality of cells incoming from the plurality of input lines are monitored to detect an output line in a congestion state. Upon detection of the output line in an congestion state, congestion information indicating the output line in the congestion state is generated and added to the output cells. An input buffer control circuit derives the congestion information from the received cell, and performs buffering of a cell or cells in an input buffer, which cells are distributed to the output line in the congested state, among cells input from the input line.