Performance Evaluation of Rate-Based Congestion Control Methods in ATM Networks

An ATM technology realizes B-ISDN by asynchronously treating various multimedia information such as data, voice and video. In ATM networks, traffic management is an important issue to utilize network resources efficiently, and ABR traffic is indispensable for data communication and most of existing applications. Rate-based congestion control is a promising scheme to incorporate ABR traffic into ATM networks because of its simplicity and scalability from local area to wide area ATM networks. In this paper, we first present a historical overview of rate-based congestion control algorithms developed in the ATM Forum. Scope of this survey includes FECN-based and BECN-based schemes, and binary feedback and explicit rate setting schemes. A summary for fairness definitions for ABR traffic is also presented. In this survey, we show how the current standard mechanism regarding the traffic management is exploited. Then, we quantitatively evaluate the performance of rate-based congestion control method in both initial transient and steady state by using an analytical approach to exhibit its effectiveness. Three types of switch algorithms suggested in the standard are considered. Through numerical examples, we show the effect of the number of active connections and the propagation delays on buffer requirements for ATM switch depending its algorithm. It is also emphasized that appropriate control parameter settings are essential for the rate-based congestion control to offer a proper traffic management tool in an ATM network environment.