ATM communication device and ATM communication network system with terminal devices having uniquely assigned virtual channel identifiers

摘要

An asynchronous transfer mode (ATM) communication network system is constructed by connecting a plurality of ATM terminal communication devices to each other through connections. Each ATM terminal communication device has a transmission function to transmit an output ATM cell and a receiving function to receive an input ATM cell. Each ATM terminal communication device includes memory including a connection control table having, for each ATM terminal communication device, an assigned virtual path identifier and an assigned virtual channel identifier; and an ATM cell transmission section for transmitting an output ATM cell including the virtual path identifier assigned to the ATM terminal communication device and the virtual channel identifier assigned to other ATM terminal communication devices, the virtual path identifier indicating the ATM terminal communication device as a transmitter of the output ATM cell, and the virtual channel identifier indicating the other ATM terminal communication device as a receiver of the output ATM cell. Each ATM terminal communication device further includes an ATM cell receiving section for comparing a virtual channel identifier of an input ATM cell with the virtual channel identifier assigned to the ATM terminal communication device, trapping the ATM cell when the virtual channel identifier of the input ATM cell matches the virtual channel identifier of the ATM terminal communication device, and discarding the input ATM cell when the virtual channel identifier of the input ATM cell does not match the virtual channel identifier of the ATM terminal communication device. The ATM terminal communication devices form a point to multipoint connection for a virtual path identified by the virtual path identifier of the output ATM cell transmitted from the ATM terminal communication device.