A Rate-based Switch Algorithm with Delay Adjustment for Abr Traac to Achieve Max-min Fairness

All the current rate-based proposals suggest to adjust the source transmission rate based on the received RM cell immediately. However, this approach may lead to overloading of the bottleneck switch. We propose that the adjustment should be delayed. The amount of delay depends on the source-to-bottleneck separations of diierent connections, which can be obtained during the call setup. Based on our Max-Min scheme 2] that can rapidly achieve the fair share allocation, a new rate-based switch mechanism is proposed to take into account of the delay. With this, overloading of the bottleneck switch due to the diierent source-to-bottleneck separations can be avoided and thus, the peak queue length of the bottleneck switch can be minimized. 1 Problem Deenition Under the current rate-based ow control framework suggested by ATM Forum, the switches calculate the proper submission rates for diierent VCs passing through it. This information is sent to the sources via the RM cells. The sources immediately adjust their allowed cell rates (ACRs) after receiving the RM cells. However, since diierent VCs may have diierent bottleneck-to-source separations, immediate adjustment of ACRs after receiving the RM cells may be hazardous. Consider Figure 1, there are a set of VCs passing through a bottleneck switch. The delays between the switch and the source end systems (SESs) of VCs a and b are Delay a and Delay b (where Delay b Delay a), respectively. Suppose there is a change in