Static and dynamic scheduling in an asynchronous transfer mode communication network

摘要

A communication subsystem is disclosed including a static scheduler and a dynamic scheduler. The static scheduler accesses a scheduling list that specifies either a virtual circuit or a dynamic scheduling indication for each cell slot on a communication link. The static scheduler selects the virtual circuit specified by the scheduling list if the scheduling list specifies the virtual circuit for the cell slot and the dynamic scheduler selects a virtual circuit from a dynamic scheduling list for transfer of the outbound communication cell if the scheduling list specifies the dynamic scheduling indication for the cell slot. The communication subsystem also includes a counter that counts if an idle communication cell is transferred over the communication link due to an underrun such that the virtual circuit specified by the dynamic scheduling list is skipped if the counter indicates the underrun.