Patent ID: 6205145
Filing Date: 2001-03-20
Classification: H04L,H04Q

Abstract:
A fibre channel fabric for interchanging a frame by dividing a connectionless, variable length frame into fixed length cells without carrying out calling setup and/or releasing command between termination nodes, to thereby interchange cells, and further by reconstructing the thus interchanged cells into an original frame, said fibre channel fabric comprising:(a) fibre channel interface control means for communicating with a termination node or another fibre channel fabric to control a fibre channel in protocol;(b) input data buffer means for temporarily storing a frame received from said termination node or said another fibre channel fabric;(c) cell producing means for dividing the thus received frame into fixed length cells;(d) cell switch means for interchanging data at the unit of a fixed length cell;(e) frame constructing means for reconstructing an original frame of said fixed length cells transmitted from said cell switch means;(f) output data buffer means for temporarily storing a frame transmitted from said frame constructing means; and(g) congestion controlling means for monitoring a load exerted on said cell switch means to thereby avoid congestion, wherein said congestion controlling means comprises(g1) flag register means having the bit number equal to the number of I/O ports: and(g2) a bus arbitrating and controlling means for receiving access requirements transmitted from said cell producing means and said frame constructing means to said flag register means, arbitrating said access requirements and transmitting arbitration results to a requester, controlling an address/data bus through which said cell producing means and said frame constructing means are communicated with said flag register means, in accordance with said arbitration results, to thereby control writing to and reading out of said flag register means, checking a value of a bit in said flag register means, and allowing use of said output data buffer means in accordance with said value of said checked bit.