Multirate Scheduling for Guaranteed and Predictive Services in ATM Networks

We propose a multirate service mechanism that allows a session to be served at different rates at different times. Applications generating bursty data, such as VBR video, can take advantage of multirate service by requesting for a peak rate of service for brief periods of bursty arrivals and a much lower average rate of service for all other times. Consequently, the applications can improve their delay performance without reserving peak bandwidth for the entire duration of the sessions. Furthermore, the scheduler can multiplex the peaks and the lulls in service rates of different sessions and there by increasing the utilization of the system. Using MPEG video traces from a number of applications, we show that our scheme outperforms Packet-by-packet Generalized Processor Sharing (PGPS) in terms of number of connections admitted, while providing the same level of service guarantees. We also investigate the performance of multirate service when service quality need not be guaranteed. We r..