Patent ID: 7180857
Filing Date: 2007-02-20
Classification: H04L

Abstract:
1. A flow control apparatus having a network of switching hubs each having a plurality of ports, each port formed of an input section which receives data packets from a data communication link and an output section which transmits data packets to said data communication link, with said switching hubs interconnected in a hierarchy for controlling transfer of data packets between respective terminals within each of a plurality of terminal groups, each said data packet including a group identifier, and each of said switching hubs having at least one group-multiplexing port which is configured to operate on data packets of said plurality of terminal groups based upon use of said group identifiers; wherein each switching hub comprises congestion judgement means for detecting occurrence of a congestion status at an output section of one of said ports, with said judgement being performed respectively separately for each of said terminal groups, and for determining specific one of said terminal groups as having caused said congestion status, and congestion notification packet outputting means for outputting a congestion notification packet which contains pause time information and is directed to said specific terminal group for controlling one or more terminals within the specific terminal group at once.