Abstract :
IBM System/360 I/O architecture was designed at a time when relatively little was known about structured programming and hierarchically constructed operating systems. These techniques have been used in an operating systems project begun some 2–1/2 years ago in Canada to implement an I/O Supervisor which models the hierarchy present in the I/O hardware. The interfaces between the various software modules suggest improvements to the System/360/370 I/O architecture, which are made feasible by current microprocessor technologies.
