Patent ID: 6912603

Claim:
A transmitting apparatus having a buffer for storing frame data that enters from a first external device, a transceiver for subjecting data read out of the buffer to predetermined transmit processing and sending the processed data to a second external device via a transmission line, and for subjecting a signal that enters from a transmission line to predetermined receive processing and outputting the processed signal, and a frame creation unit for putting the data output from the receive side of the transceiver into the form of a frame and sending the frame to the first external device, said apparatus comprising: a band controller for monitoring an amount of data stored in the buffer and commanding that a flow-control start request frame be created when the amount of stored data has exceeded a first set value; a flow-control-frame creation unit for creating a flow-control start request frame and sending it to the first external device on the basis of the command, and for creating a flow-control start request frame and sending it to the first external device without performing flow control when a flow-control start request signal enters from the transmission line; and means for sending a flow-control start request signal to the second external device via the transmission line without performing flow control when a flow-control start request frame enters from the first external device.