Non-Preemptive Priority Scheduler With Multiple Thresholds for Network Routers

Abstract

The vast variety of applications available and being developed for computer networks have different quality of service requirements. One of the most significant ways to satisfy the needs of the applications is the packet scheduling algorithms employed by the network routers. By allocating router resources to the applications packet schedulers try to improve the quality of service needs of the applications. Thus the delays can be reduced or the reliability of the applications can be increased by reducing packet losses. Priority schedulers are able reduce the delay and losses for high priority applications. On the other hand for low priority applications they introduce the starvation problem. Low priority application packets can face excessive delays and losses. In this paper a non-preemptive priority scheduler with multiple thresholds (PRMT) is proposed. The PRMT scheduler needs only a single queue with predefined threshold levels for different priority applications. The PRMT scheduler eliminates the starvation problem of low priority applications without a significant impact on the high priority applications.