Patent ID: 6859459

Claim:
A high-speed/high-reliability Ether transmission system comprising a plurality of Ether cables, a local bus connected to an information processing device and having a higher speed than that of said Ether cables, and an I/F apparatus, said Ether cables being connected through said I/F apparatus to said local bus, wherein said I/F apparatus comprises a plurality of Ether ports connected to said Ether cables, a bus port connected to said local bus, a controller connected to said Ether ports and said bus port, and a MAC to port table memory for storing a corresponding relationship between a MAC address to which an Ether frame is to be transferred and said Ether ports or said bus port to which said frame is to be transferred, wherein said controller refers to said MAC to port table memory when it receives an Ether frame banns a MAC address to which said frame is to be transferred, and if said MAC address to which said frame is to be transferred is stored in said MAC to port table memory, it transmits said Ether fire to a port to which said frame is to be transferred corresponding to said MAC address, or if said MAC address to which said frame is to be transferred is, not stored, it transmits said Ether frame to ports except a port which has received said Ether frame and stores a corresponding relationship between a MAC address from which said Ether frame has been transferred and said port which has received said Ether frame in said MAC to port table memory, and when it receives an Ether frame having a broadcast MAC address, it transmits said Ether frame to all ports except a port which has received said Ether frame and stores a corresponding relationship between a MAC address from which said Ether frame has been transferred and said port which has received said Ether frame in said MAC to port table memory; and wherein said controller also stores a counter value for specifying one of a plurality of said Ether ports in turn at transmission of an Ether frame to said Ether ports when said plurality of Ether ports correspond to a single MAC address to which said frame is to be transferred in a corresponding relationship between a MAC address to which said frame is to be transferred and Ether ports to which said frame is to be transferred stored in said MAC to port table memory, and increments and updates said counter value each time an Ether frame is transferred to one of said plurality of ether ports.