Presently disclosed is an apparatus and method for returning control of
bandwidth allocation and packet scheduling to the routing engine in a
network communications device containing an ATM interface. Virtual
circuit (VC) flow control is augmented by the addition of a second flow
control feedback signal from each virtual path (VP). VP flow control is
used to suspend scheduling of all VCs on a given VP when traffic has
accumulated on enough VCs to keep the VP busy. A new packet segmenter is
employed to segment traffic while preserving the first in, first out
(FIFO) order in which packet traffic was received. Embodiments of the
invention may be implemented using a two-level (per-VC and per-VP)
scheduling hierarchy or may use as many levels of flow control
feedback-derived scheduling as may be necessitated by multilevel
scheduling hierarchies.