Atm communication apparatus and method of controlling congestion in a communication network using the atm communication apparatus

Abstract

An ATM communication apparatus excellent in reliability and economical efficiency and capable of performing congestion control at a high speed in an asynchronous transfer mode (ATM) communication network. For this purpose, there are provided in the ATM communication apparatus a mechanism for identifying a cell transmitting origin that has caused a congestion when the congestion is detected in a communication node and a mechanism for newly generating a congestion notifying RM cell and transmitting it directly to the cell transmitting origin, and there is provided a congestion control function for generating and sending an RM cell immediately to a communication terminal or a communication apparatus that is transmitting a cell which causes the congestion within a communication apparatus having a congestion cell buffer at the time of generation of a congestion of a cell buffer within the node. A communication network is structured of this ATM communication apparatus, and, at the time of a congestion state of a communication apparatus, the response period of time required from a communication terminal or a communication apparatus which is transmitting a cell which causes a congestion receives an RM cell until the cell transmission speed is lowered is shortened. Thus, the quantity of cell buffers provided in a communication apparatus is reduced.