Patent ID: 7397764

Claim:
A gateway for coupling a fiber channel (FC) network and a wide area network (WAN), comprising: an FC interface adapted to interface with the FC network; a WAN interface adapted to interface with the WAN; a converter adapted to (1) convert FC data received by the FC interface into internet protocol (IP) over WAN (IP/WAN) data for transmission by the WAN interface to the WAN and (2) convert IP/WAN data received by the WAN interface into FC data for transmission by the FC interface to the FC network; and a flow-control manager adapted to control the rate at which the converter converts FC data into IP/WAN data, wherein: if a backup is created in a queue of outgoing FC data in the FC interface as a result of the FC network withholding buffer credits for the FC interface, then (i) the FC interface communicates corresponding congestion information to the WAN interface, which causes (ii) the WAN interface to transmit WAN congestion information to the WAN to instruct the WAN to decrease the rate at which the WAN transmits IP/WAN data to the WAN interface; and if the WAN interface receives WAN congestion information from the WAN, then (i) the WAN interface communicates corresponding congestion information to the flow-control manager, which causes (ii) the converter to decrease the rate at which the converter converts FC data into IP/WAN data, which can create a backup in a queue of incoming FC data in the FC interface, in which case the FC interface will begin to withhold buffer credits for the FC network to decrease the rate at which the FC network transmits FC data to the FC interface.