An efficient, cost effective method and apparatus for performing resource
allocation of available bit rate (ABR) virtual circuit (VC) in an
asynchronous transfer mode (ATM) network includes an explicit rate switch
process performed at at least one switch of an ABR VC. The process
provides a fast and more accurate computation of the number of active VCs
in an ATM network. Furthermore, the fair share allocation is calculated at
the switch in a way that is efficient and lends itself easily to
implementation in hardware. For example, in one embodiment, the fair share
is implemented using a series of counters and registers controlled by a
state machine. This simple hardware implementation enables fast
convergence to a current final state so that timely accurate resource
utilization and allocation to the ABR VCs can be determined.