Patent ID: 6628662
Filing Date: 2003-09-30
Classification: H04L

Abstract:
A method for arbitrating data transfers between a plurality of devices connected via electronically isolated buses at a switch, said method comprising the steps of:interposing a plurality of arbitration controllers between a plurality of devices and a switch having a plurality of ports to which said plurality of devices are connected, each of said plurality of arbitration controllers corresponding to a respective one of a subset of said plurality of ports; selecting a plurality of data transfer operations in each bus cycle, each data transfer operation being selected independently by a respective one of said plurality of arbitration controllers from among a respective plurality of data transfer operations associated with the respective port to which the respective arbitration controller corresponds; detecting collisions between said plurality of data transfer operations selected in each bus cycle by said arbitration controllers; enabling said switch for any of said selected data transfer operations between which collisions are not detected; enabling said switch, in any given bus cycle, for only one of said selected data transfer operations between which collisions are detected and deferring any said selected data transfer operations for which said switch is not enabled; and prioritizing said deferred selected data transfer operations within said plurality of arbitration controllers, such that for a subsequent selection of said deferred selected data transfer operations said switch is enabled for said deferred selected data transfer operations.