The novel credit-based adaptive flow control method and system for multi-stage,
multi-dimensional, data switching architecture. The method and system of the present
invention estimates and balances data flow in the switch architecture by using
statistical information derived from the normal switching operation without requiring
specific information from the previous stage. The multi-stage multi-dimensional
switching architecture of the present invention includes three stages. The first
and third stages are the buffering stages, and the second stage acts as a buffer-less
crossbar switch node. Each stage includes an array of switching elements, and each
element includes either a queuing processor or an arbitration processor arranged
to progressively refine estimates of the data traffic from switch elements in the
first stage by the second stage. The second stage maintains the statistic of valid
traffic arrival and departure, and feedback grant information bit to the first
stage. The first stage treats every grant information as credit for each data departure
to the second stage, and sends the data if there is a grant credit available. The
adaptive filtering process adjusts a threshold adaptively, rendering the statistical
properties to resemble a chosen probability distribution.