  The OSU scheme is a rate-based congestion avoidance scheme for ATM networks
using explicit rate indication. This work was one of the first attempts to
define explicit rate switch mechanisms and the Resource Management (RM) cell
format in Asynchronous Transfer Mode (ATM) networks. The key features of the
scheme include explicit rate feedback, congestion avoidance, fair operation
while maintaining high utilization, use of input rate as a congestion metric,
O(1) complexity. This paper presents an overview of the scheme, presents those
features of the scheme that have now become common features of other switch
algorithms and discusses three extensions of the scheme.
