Input/output optical fiber serial interface link that selectively transfers data in multiplex channel path mode or high speed single channel path mode

摘要

An input/output data transfer system capable of integrating input/output data transfer on a plurality of input/output interface cables into data transfer on a single serial input/output interface cable for substantially reducing the number of input/output interface cables required for a host computer system. A multiplexer channel device is provided with a plurality of channels which serve as logical channels corresponding to conventional physical channel paths from a viewpoint of an operating system running on the host computer system. A multiplexer port device is provided with a plurality of input/output ports on a switching device or input/output device, each of these channels and ports shares a large-capacity input/output interface, and a channel path multiplexing function is performed for enabling frame-by-frame multiplexing and simultaneous input/output operations on plural channels. For each of logical channel paths multiplexed on the large-capacity link, a logical connection is established to provide compatibility with conventional input/output operations, and a data transfer capacity bandwidth of the large-capacity link is always allocated optimally to one or more active channels.