Dynamic window-constrained scheduling for multimedia applications

Abstract

This paper describes an algorithm, called dynamic window-constrained scheduling (DWCS), designed to meet the service constraints on packets from multiple, network-bound media streams with different performance objectives. Using only two attributes, a deadline and a loss-tolerance per packet stream, DWCS: can limit the number of late packets over finite numbers of consecutive packets in loss-tolerant or delay constrained, heterogeneous traffic streams; does not require a priori knowledge of the worst-case loading from multiple streams to establish the necessary bandwidth allocations to meet per-stream delay and loss constraints; and can exhibit both fairness and unfairness properties when necessary. In fact, DWCS can perform fair-bandwidth allocation, static priority (SP) and earliest-deadline first (EDF) scheduling. The paper shows the effectiveness of DWCS using a streaming video application, running over ATM.